fix(webui): P2 system types in a side-by-side pane only show, never switch (#1873 )

U5 draws the organization dashboard into a side-by-side pane, and the System types section came with it: Enable and Disable buttons that wrote to the selected organization whatever the pane showed, a heading id repeated in both panes, and a Settings Open button that focused the first pane's section. A pane now shows its own organization's types with no switch and says to change them from the full view, as U5 does for the bus restart. The heading id carries the pane's prefix, Open focuses the section in its own dashboard, and the click handler and the post-write repaint ignore panes.
test(webui): answer the project system-types read in the W15 integration fixture (#1873 )
2026-11-10 14:44:02 -06:00 · 2026-11-10 14:41:53 -06:00 · 2026-11-10 14:41:53 -06:00 · 2026-11-10 14:41:53 -06:00 · 2026-11-10 14:07:05 -06:00 · 2026-11-10 14:07:05 -06:00
20 changed files with 2127 additions and 70 deletions
@@ -0,0 +1,212 @@
+# System-type toolsets at launch
+
+Status: design only. Nothing here is built and no `roles/` or contract file is
+changed. Prepared 2026-11-10 against `refactor` `8630b8dfc` for phase P2 of
+#1873 (unified workspace). PRD requirement: REQ-SYS-2, "An agent working in a
+project gets the toolsets of the system types that project uses."
+
+## What exists today
+
+- **Modules.** `installedSystemTypes()` (`packages/plugins/src/system-types.mjs`)
+  loads every installed `system-type` module and returns
+  `{id, label, description, toolsets}`. It is fail-closed: a refused module, a
+  missing or extra key, or a toolset name that fails `NAME` throws
+  `system-type-invalid`. All five shipped modules (business-management, coding,
+  creative-writing, marketing, montage) declare `toolsets: []`.
+- **Organization enable.** The organization file's
+  `plugins['system-type']` holds the enabled ids. `plugins.set` writes it
+  through the organization writer behind the owner fence
+  (`organization-system-types-human-only`) and returns a transaction receipt.
+  The bus reads the current set with `system-types.current` on every read and
+  write, so it never trusts a stale snapshot.
+- **Project selection.** `project.system-types.set` appends a row to
+  `project_system_types` (bus store, `seq`-ordered, latest wins) and accepts
+  only enabled ids (`system-type-not-enabled`). A read returns
+  `{selected, active, inactive}`, where `active = selected ∩ enabled` and
+  `inactive = selected − enabled`.
+- **Launch.** `resolveInstance` (`packages/organization/src/resolve.mjs`)
+  starts from the role definition's `tools` and `network`, narrows them by
+  each layer's `limits.tools` and `limits.network` (system, business,
+  project, agent), and freezes the result with a digest. The role's `tools`
+  is therefore a ceiling: a launch gets those tools minus whatever a layer
+  limit removes, never more. The launcher (`packages/cli/src/launcher.mjs`) passes that
+  result to `buildBundle` (`packages/harness/src/bundle.mjs`), which writes
+  `policy.json` (`tools: builtinTools(resolved.limits.tools)`), `tools.json`
+  (typed host tools) and `manifest.json` once each (`flag: "wx"`). Typed
+  host tools (`typedTools`, `packages/harness/src/tools.mjs`) are not granted
+  by tool name: each is built only when the resolved `authority` holds the
+  action it needs.
+- **Run tasks.** `scripts/mosaic-task.mjs` validates a mission's
+  `capabilities.tools` as a ceiling and a task's `capabilities.tools` as the
+  allowlist, both drawn from `SUPPORTED_TOOLS`. A task narrows the mission.
+  It never widens it.
+
+Nothing on the launch path reads system types today, so every launch gets
+its role's tools as narrowed by the layer limits. That is the coding
+module's behavior, and the design keeps it as the default.
+
+## Resolution at launch
+
+A launch resolves its toolsets in the host-side launcher, before
+`resolveInstance` freezes the digest. In order:
+
+1. **Pick the project.** The launch's project is the one the session is
+   started for: the thread's project for a project thread, or none. A launch
+   with no single project (an organization-wide session, or a role started
+   with several code projects in scope) gets no system-type toolsets. Taking
+   the union across projects would widen one project's agent with another
+   project's tools, so the union is ruled out.
+2. **Read the active set.** The launcher asks the bus, as the host, for the
+   project's selection and computes `active = selected ∩ enabled`. `enabled`
+   comes from `system-types.current`, the same trusted read the routes use.
+   Inactive selections are dropped and recorded in the manifest. They do not
+   refuse the launch, because the owner may disable a type at any time and
+   that must not strand running work.
+3. **Load the modules.** `installedSystemTypes()` runs. If it throws
+   `system-type-invalid`, the launch refuses with that code. An active id
+   with no installed module refuses `system-type-missing`.
+4. **Map toolset names to tools.** Each active module's `toolsets` are looked
+   up in the reviewed mapping file (below). The result is a set of tool names,
+   each a member of the role vocabulary `TOOLS`
+   (`packages/organization/src/vocabulary.mjs`). Typed host tools cannot be
+   named: they stay gated by the role's `authority` actions exactly as today,
+   and a system type never changes `authority`.
+5. **Bound by the ceilings.** The role's `tools` stays the hard ceiling for
+   every effective tool, including any a system type switches on. A role may
+   hold some of its tools back for typed projects by listing them in
+   `systemTypeTools` (new, see the proposal), which must be a subset of the
+   role's `tools`. Then:
+   - `base` = (role `tools` − `systemTypeTools`), narrowed by every layer's
+     `limits.tools`, as `resolveInstance` does today;
+   - `added` = mapped tools ∩ `systemTypeTools`, narrowed by every layer's
+     `limits.tools` the same way;
+   - `effective` = `base ∪ added`;
+   - for a run task, `effective` is then intersected with the mission's
+     `capabilities.tools` and then the task's. That intersection covers
+     base tools too, as it does today.
+
+   Every term is a subset of role `tools` ∩ every layer limit, so a system
+   type can only switch on a tool the role already holds and the layers
+   already allow. Invariant 7 holds because each later step can only remove
+   entries. A role without `systemTypeTools` behaves exactly as today.
+6. **Record it.** `resolveInstance` takes the added list as an input and
+   includes `systemTypes: {project, active, dropped, toolsets, added}` in the
+   resolved object, so the digest covers it. `buildBundle` writes the same
+   block into `manifest.json`. The run record then shows which types and
+   mapping produced each tool.
+
+No step adds credentials, network reach or authority. `limits.network` and
+`authority` are computed exactly as today. A toolset that needs a credential
+gets it the way any role does, through the role file's `credentials` and a
+reviewed commit. A system type never grants one.
+
+## The mapping file
+
+The mapping is repository policy, so it lives under `roles/` and changes only
+through a reviewed commit, the same rule that governs `roles/*.json`
+(invariant 7, AGENTS.md "Role model"). Proposed path:
+`roles/toolsets/system-types.json`. It sits in a subdirectory because two
+loaders read every `roles/*.json` as a role definition
+(`instance-settings.mjs` `definitions()`, `harness/tests/tools.test.mjs`).
+A mapping file at `roles/` top level would be read as a broken role.
+
+Proposed format:
+
+```json
+{
+  "toolsetsVersion": 1,
+  "toolsets": {
+    "repository": { "tools": ["read", "write", "edit", "bash", "grep", "find", "ls"] },
+    "web-research": { "tools": ["web"] }
+  }
+}
+```
+
+The two entries are illustrations, not part of the proposal. No shipped
+module names a toolset today, so the file would ship as
+`{"toolsetsVersion": 1, "toolsets": {}}`.
+
+Rules a loader enforces, fail-closed:
+
+- Exactly the keys `toolsetsVersion` (must be `1`) and `toolsets`. Each entry
+  has exactly the key `tools`.
+- Each toolset name matches `NAME` from `packages/plugins/src/kinds.mjs`, the
+  same pattern modules must use.
+- `tools` is a non-empty list of distinct names, each in `TOOLS`. A typed
+  host tool name, or anything else, refuses `toolset-mapping-invalid` at
+  load.
+- The file is read from the release copy, like the role files, and its
+  sha256 goes into `manifest.sources`.
+
+Who may change it: a reviewed commit on the repository, landed by the lead
+with Jason's authority over role policy. An organization owner cannot change
+it at runtime, and neither the Console nor the bus has a write path to it.
+Organization owners choose which types are enabled and projects choose among
+them. The repository decides what a type's toolsets may contain.
+
+## Fail-closed behavior
+
+| Condition | Result |
+| --- | --- |
+| An installed module is refused or malformed | launch refuses `system-type-invalid` |
+| An active id has no installed module | launch refuses `system-type-missing` |
+| A module names a toolset the mapping lacks | launch refuses `toolset-unmapped` |
+| The mapping file is missing, unreadable or invalid | launch refuses `toolset-mapping-invalid`, but only when at least one active type declares a toolset; a launch with nothing to map never reads it |
+| A mapped tool is outside the role's `systemTypeTools` (and so not switched on) | the tool is dropped and recorded under `dropped`, launch continues |
+| The bus cannot answer the project's selection | launch refuses `system-types-unavailable`; it does not fall back to "no types", which could hide a missing toolset the operator expects |
+| A selection is inactive (disabled in the organization) | dropped and recorded, launch continues |
+
+The two "continue" rows are narrowing, never widening. Every row that could
+change what an agent may do refuses instead.
+
+## The coding module
+
+Coding declares `toolsets: []`. It adds nothing, and a coding project's agent
+keeps its role's tools as the layer limits narrow them: for
+`roles/coder.json` the ceiling is `read, write, edit, bash, grep, find, ls`
+with network `api-only`, the same as today. Turning the design on changes nothing for any shipped module until a
+module declares a toolset and a reviewed commit maps it.
+
+## Proposed `roles/` change (not applied)
+
+1. Add an optional V2 key `systemTypeTools` to the role schema
+   (`packages/organization/src/role.mjs`): a distinct list from `TOOLS` (same
+   check as `checkTools`, but empty is allowed) that must be a subset of the
+   role's own `tools`, or the role file refuses at load. It names the tools
+   the role holds back unless an active system type maps them. Absent means
+   `[]`: nothing is held back and no system type changes that role's tools.
+   Every existing role file stays valid and behaves as today, and
+   `checkCreative` keeps inspecting `tools`, which still bounds everything.
+
+   ```diff
+    const V2_REQUIRED = ["roleVersion", "name", "title", "contract", "tools", "network", "authority", "credentials"];
+   -const V2_KEYS = [...V2_REQUIRED, "messaging", "skills", "hireable"];
+   +const V2_KEYS = [...V2_REQUIRED, "messaging", "skills", "hireable", "systemTypeTools"];
+   ```
+
+2. Add `roles/toolsets/system-types.json` with an empty `toolsets` object, and
+   a loader beside the role loader with the checks listed above.
+3. Have `resolveInstance` accept `systemTypes` (the launcher's step 1-4
+   result) and apply step 5. Have `buildBundle` copy the block into the
+   manifest. `scripts/mosaic-task.mjs` already bounds tools by mission and
+   task. It would apply that filter to the final effective set.
+
+No contract under `contracts/` changes: the constitution's least-privilege
+rule already covers this. The design adds no grant path: the effective set
+stays within role `tools` and every layer limit, and `authority`, network and
+credentials are untouched. What it does add is a runtime input (the
+project's active system types) that can switch a held-back tool on, so a
+role author who lists a tool in `systemTypeTools` is deciding that an
+organization owner's enable plus a project's selection may turn it on. Each of the
+three steps is a reviewed change to role policy and needs Jason's sign-off
+before it is built.
+
+## Open points for the build
+
+- Business-file projects (`b.projects`, used for checkouts) and bus projects
+  (UUIDs in `project_system_types`) are separate records today. Step 1 needs
+  the launch to carry the bus project id of the thread it serves. The build
+  should confirm how a project thread names its project at launch before
+  wiring step 2.
+- A running session keeps the toolsets it launched with. Disabling a type
+  takes effect at the next launch, which matches how role changes behave.
@@ -5,6 +5,7 @@ import { startServer, previewOptions, proofOptions, DEFAULT_BOARD } from './serv
 import { busCaller, busBusiness, userCaller, consoleCall } from './bus.mjs';
 import { organizationConsole } from './organizations.mjs';
 import { consoleBus, userOptionsFor, agentCaller, TESTER_AGENT_VERBS } from './console-bus.mjs';
+import { SYSTEM_TYPE_VERBS } from './system-types-http.mjs';
 import { consoleAccess } from './access.mjs';
 import { accessContextFor } from '../../cli/src/access.mjs';
 import { accessFilePath, loadAccess } from '../../organization/src/access.mjs';
@@ -169,6 +170,9 @@ try {
        // The owner reads request status on the selected organization's bus, as on the root Console. Request
        // writes stay off: the README "Console actions" inventory marks them unavailable for the organizations release.
        requestRead: session.user === undefined ? consoleCall({ dataRoot: root, socket: paths.socket, business: id }) : null,
+        // Phase P2 (#1873): the owner's System types writes, the organization's enable switch (plugins.set
+        // with its revision) and a project's selection, over the owner's human transport under --send only.
+        systemTypesWrite: session.user === undefined && sendOn ? agentCaller(owner, SYSTEM_TYPE_VERBS) : null,
        reads: consoleReads({ root: REPO, queueRoot: options.checkout ?? REPO, system, configDir: configDir(), rolesDir: rolesDir(), business: id, orgRoot: root }),
      };
    },
@@ -1449,7 +1449,6 @@
    if (n === 0 && window.MosaicOrg) return window.MosaicWorkspace.home();
    if (a === 'projects' && n === 1 && window.MosaicOrg) return window.MosaicWorkspace.projectsPage(q);
    if (a === 'organization' && n === 1 && window.MosaicOrg) return window.MosaicWorkspace.dashboard();
-    if (a === 'side-by-side' && n === 1 && window.MosaicOrg) return `${head('Side by side', 'Not built yet.')}${empty('Side by side is not built yet.', 'It arrives with a later unified workspace update. Projects and Agents work today.')}`;
    if (a === 'inbox' && n === 1 && window.MosaicOrg) return window.MosaicWorkspace.inboxPage(q);
    if (a === 'tasks' && n === 1 && window.MosaicOrg) return window.MosaicTasksBoard.view();
    if (a === 'inbox' && n === 1) return inboxView(get);
@@ -1542,6 +1541,15 @@
    window.MosaicChat?.leave(chatPath);
    if (path === '/business') { location.replace('#/settings/business'); return; }
    if (path === '/settings/display') { location.replace('#/settings/appearance'); return; }
+    // U5: Side by side draws its own two panes (panes.js); every other page stops their polling.
+    if (path !== '/side-by-side') window.MosaicPanes?.unmount();
+    else if (window.MosaicOrg && window.MosaicPanes) {
+      const fresh = navigated || shown !== path;
+      shown = path;
+      if (fresh) { unmountEditor(); await window.MosaicPanes.mount($('bus-view'), query, { navigated }); }
+      else window.MosaicPanes.refresh();
+      return;
+    }
    if (chatPath === '/chat' || chatPath.startsWith('/chat/') || /^\/projects\/[0-9a-f-]+\/(?:settings|conversations|tasks|requirements|files)$/i.test(chatPath)) {
      // Re-read the scoped capability as the Console and bus recover. A failed read
      // withdraws the control; the chat renderer retains the draft across repaint.
@@ -620,7 +620,7 @@
      html += p && !c.refused && redesigned ? window.MosaicProjects.header(p, c.section, c.threads) : heading(p?.name ?? 'Project unavailable');
      if (p && !c.refused) {
        if (p.archived && redesigned && !c.canSend) html += '<p class="project-panel" role="status">This project is archived. Its saved conversations and records stay readable.</p>';
-        if (c.settings) html += `<p><a href="#/projects/${esc(c.id)}">Project overview</a></p><h2>Project information</h2><p>Repository: ${txt(p.repo || 'Not linked')}</p><div data-chat-remote>Repository setting unavailable.</div>`;
+        if (c.settings) html += `<p><a href="#/projects/${esc(c.id)}">Project overview</a></p><h2>Project information</h2><p>Repository: ${txt(p.repo || 'Not linked')}</p><div data-chat-remote>Repository setting unavailable.</div><div data-chat-system-types>System types unavailable.</div>`;
        else if (c.section === 'conversations' && redesigned) html += `<div class="project-section-title"><h2>Conversations</h2></div><div data-project-conversations>${c.threads.filter(t=>!t.shared && t.project===p.id).map(t=>`<a class="project-conversation-row" href="${threadPath(esc(t.id))}" data-conversation-id="${esc(t.id)}"><span class="project-conversation-icon" aria-hidden="true">◌</span><span><strong>${txt(t.name)}</strong><small>With ${txt(t.instance)}</small></span><span data-conversation-status></span><span aria-hidden="true">›</span></a>`).join('') || '<p>No conversations yet. Start one to begin work.</p>'}</div>${p.archived ? '' : `<details class="project-new-conversation"${location.hash.includes('new=1')?' open':''}><summary class="btn primary">New conversation</summary>${creation('thread', c.id)}</details>`}<h2>Shared with me</h2>${c.threads.some(t=>t.shared && t.project===p.id)?threads(c.threads.filter(t=>t.shared && t.project===p.id)):'<p>Nothing is shared with you yet.</p>'}`;
        else if (c.section === 'conversations') html += '<h2>Conversations</h2>' + threads(c.threads.filter(t => !t.shared)) + (p.archived ? '' : creation('thread', c.id));
        else if (redesigned) html += '<div data-project-content>Reading…</div>';
@@ -684,6 +684,9 @@
    const remote = c.container.querySelector('[data-chat-remote]');
    const project = c.projects.find(p => p.id === c.id);
    if (remote && roomOwner() && typeof window.MosaicProjectRemote?.mount === 'function') { remote.replaceChildren(); window.MosaicProjectRemote.mount({ container: remote, projectId: c.id, repositoryKey: project?.repo ?? null, projectArchived: !!c.projectArchived, preserve: true }); }
+    // Phase P2 (#1873): the project's System types selection, the owner's, mounted like the remote.
+    const types = c.container.querySelector('[data-chat-system-types]');
+    if (types && roomOwner() && typeof window.MosaicSystemTypes?.mount === 'function') window.MosaicSystemTypes.mount({ container: types, projectId: c.id, archived: !!c.projectArchived });
    if (!window.MosaicOrg && (!redesigned || c.kind !== 'project' || c.settings || c.projectArchived)) window.MosaicProjectArchive?.mount(c.container, c);
    if (redesigned && c.kind === 'project' && c.projectArchived && !c.settings) {
      const controls = c.container.querySelector('.project-archive-control');
@@ -6,8 +6,8 @@
 <link rel="stylesheet" href="/project-archive.css"><link rel="stylesheet" href="/projects.css">
 <link rel="stylesheet" href="/processing.css"><script src="/processing.js" defer></script>
 <link rel="stylesheet" href="/org-create.css"><script src="/org-create.js" defer></script>
-<link rel="stylesheet" href="/onboarding.css"><script src="/onboarding.js" defer></script>
-<script src="/workspace-data.js" defer></script><script src="/workspace.js" defer></script><script src="/tasks-board.js" defer></script><script src="/console-restart.js" defer></script><script src="/display.js" defer></script><script src="/inbox.js" defer></script><script src="/files.js" defer></script><script src="/project-remote.js" defer></script><script src="/federation.js" defer></script><script src="/brand.js" defer></script><script src="/app.js" defer></script><script src="/markdown-preview.js" defer></script><script src="/projects.js" defer></script><script src="/chat.js" defer></script><script src="/project-archive.js" defer></script><script src="/agents.js" defer></script><script src="/bus.js" defer></script><script src="/requests.js" defer></script></head>
+<link rel="stylesheet" href="/onboarding.css"><script src="/onboarding.js" defer></script><link rel="stylesheet" href="/panes.css">
+<script src="/workspace-data.js" defer></script><script src="/workspace.js" defer></script><script src="/tasks-board.js" defer></script><script src="/console-restart.js" defer></script><script src="/display.js" defer></script><script src="/inbox.js" defer></script><script src="/files.js" defer></script><script src="/project-remote.js" defer></script><link rel="stylesheet" href="/system-types.css"><script src="/system-types.js" defer></script><script src="/federation.js" defer></script><script src="/brand.js" defer></script><script src="/app.js" defer></script><script src="/markdown-preview.js" defer></script><script src="/projects.js" defer></script><script src="/chat.js" defer></script><script src="/project-archive.js" defer></script><script src="/agents.js" defer></script><script src="/panes.js" defer></script><script src="/bus.js" defer></script><script src="/requests.js" defer></script></head>
 <body>
 <div hidden aria-hidden="true"><select id="palette"></select><select id="mode"><option value="system">system</option><option value="light">light</option><option value="dim">dim</option><option value="dark">dark</option></select></div>
 <a class="skip" href="#main">Skip to content</a>
@@ -0,0 +1,83 @@
+/* Side by side (U5, sample 07 "EXT 8"): a bar, then two panes with a divider between them. Each pane
+   has its own header with the organization's mark and edge, and its own scroll. One pane and a
+   shown-pane switch on a phone. Loaded after shell.css; every rule is scoped to the side-by-side page. */
+html[data-organizations] .content:has(> #bus-view > .sbs){padding:0}
+html[data-organizations] .sbs{margin:0;display:flex;flex-direction:column;min-height:0;height:calc(100vh - var(--bar-h,53px) - var(--foot-h,33px))}
+html[data-organizations] .sbs .panebar{display:flex;align-items:center;gap:10px;padding:8px 14px;border-bottom:1px solid var(--line);background:var(--canvas);flex-wrap:wrap}
+html[data-organizations] .sbs .panebar h1{font-size:16px;font-weight:700;margin:0;line-height:1.4}
+html[data-organizations] .sbs .panebar h1:focus{outline:none}
+html[data-organizations] .sbs .panebar .note{font-size:13px;color:var(--muted)}
+html[data-organizations] .sbs .panebar [data-pane-add]{margin-left:auto}
+html[data-organizations] .sbs .ws-seg.pane-tabs{display:none;margin-left:0}
+html[data-organizations] .sbs .pane-tabs>button{gap:5px;max-width:44vw}
+html[data-organizations] .sbs .pane-tabs>button>span:last-child{overflow:hidden;text-overflow:ellipsis}
+
+html[data-organizations] .panes{--sbs-a:1fr;--sbs-b:1fr;display:grid;grid-template-columns:minmax(0,1fr);flex:1;min-height:0}
+html[data-organizations] .panes.two{grid-template-columns:minmax(0,var(--sbs-a)) 1px minmax(0,var(--sbs-b))}
+html[data-organizations] .pane{display:flex;flex-direction:column;min-width:0;min-height:0}
+html[data-organizations] .pane[hidden]{display:none}
+html[data-organizations] .pane-h{display:flex;align-items:center;gap:8px;padding:8px 14px;border-bottom:1px solid var(--line);background:var(--surface);box-shadow:inset 0 3px 0 var(--org,var(--line));min-width:0}
+html[data-organizations] .pane-h .ttl{font-weight:700;color:var(--strong,var(--text));overflow:hidden;text-overflow:ellipsis;white-space:nowrap;min-width:0;flex:0 1 auto}
+html[data-organizations] .pane-h .ttl small{font-weight:500;color:var(--muted);margin-left:6px;font-size:inherit}
+html[data-organizations] .pane-h [data-pane-state]:empty{display:none}
+html[data-organizations] .pane-pick{flex:0 1 180px;min-width:0;max-width:220px;margin-left:auto;font:500 12px/1.4 var(--font);color:var(--text);background:var(--canvas);border:1px solid var(--line);border-radius:var(--r);padding:3px 6px;min-height:0}
+html[data-organizations] .pane-h .tools{display:flex;gap:2px;flex:none}
+html[data-organizations] .pane-tool{display:inline-grid;place-items:center;width:26px;height:26px;border-radius:var(--r);color:var(--muted);border:0;background:none;padding:0;min-height:0;cursor:pointer}
+html[data-organizations] .pane-tool:hover{background:var(--raised);color:var(--text)}
+html[data-organizations] .pane-tool[hidden]{display:none}
+html[data-organizations] .pane-tool svg.i{width:15px;height:15px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
+html[data-organizations] .pane-line{margin:0;padding:6px 14px;border-bottom:1px solid var(--line);font-size:13px;color:var(--text);background:color-mix(in srgb,var(--warn,#b7791f) 12%,var(--surface))}
+html[data-organizations] .pane-line[hidden]{display:none}
+html[data-organizations] .pane-body{overflow:auto;padding:14px;min-height:0;flex:1}
+html[data-organizations] .pane-body:focus{outline:none}
+html[data-organizations] .pane-body:focus-visible{outline:2px solid var(--focus,var(--action));outline-offset:-2px}
+/* A page inside a pane is a section of the side-by-side page: smaller headings, no page chrome. */
+html[data-organizations] .pane-body .ws h1{font-size:20px}
+html[data-organizations] .pane-body .chat-area.pane-project{display:block;height:auto;min-height:0;overflow:visible;padding:0}
+/* A project in a pane is compact (sample 07): the pane header already names the project and its
+   organization, so the page heading stays only for assistive technology and focus, the full-page
+   actions give way (North star and PRD are on the Requirements tab, Settings in the full view), and
+   the tabs, measures and current work come first. Project pages size some parts from the window
+   (projects.css); in a pane they size from the pane. */
+html[data-organizations] .pane-body{container-type:inline-size}
+html[data-organizations] .pane-body .project-header{display:block;width:auto;max-width:100%;margin:0 0 6px;padding:0}
+html[data-organizations] .pane-body .project-header .project-heading,html[data-organizations] .pane-body .project-header .project-heading>div{display:block}
+html[data-organizations] .pane-body .project-header-icon,html[data-organizations] .pane-body .project-actions{display:none}
+html[data-organizations] .pane-body .project-header h1{position:absolute;width:1px;height:1px;margin:-1px;padding:0;border:0;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
+html[data-organizations] .pane-body:has(.project-header h1:focus-visible){outline:2px solid var(--focus,var(--action));outline-offset:-2px}
+html[data-organizations] .pane-body .project-header .project-heading p{margin:0;font-size:13px;color:var(--muted)}
+html[data-organizations] .pane-body .project-tabs a{min-height:40px;padding:0 12px;font-size:14px}
+html[data-organizations] .pane-body .project-metrics{grid-template-columns:repeat(2,minmax(0,1fr));margin-top:10px;padding:6px 0}
+html[data-organizations] .pane-body .project-metrics a{padding:4px 12px;border-right:0;border-bottom:0;line-height:1.3}
+html[data-organizations] .pane-body .project-metrics a span,html[data-organizations] .pane-body .project-metrics small{font-size:12px;overflow-wrap:anywhere}
+html[data-organizations] .pane-body .project-metrics strong{font-size:20px}
+html[data-organizations] .pane-body .project-metrics p{margin:6px 12px 0;padding-top:6px}
+html[data-organizations] .pane-body .project-columns{grid-template-columns:minmax(0,1fr);gap:14px;margin-top:12px}
+html[data-organizations] .pane-body .project-columns h2{font-size:16px;margin:12px 0 8px}
+html[data-organizations] .pane-body .project-columns h3{font-size:14px}
+html[data-organizations] .pane-body .project-columns .project-section-title h2,html[data-organizations] .pane-body .project-columns aside>h2:first-child{margin-top:0}
+@container (min-width:560px){
+  html[data-organizations] .pane-body .project-metrics{grid-template-columns:repeat(4,minmax(0,1fr))}
+  html[data-organizations] .pane-body .project-metrics a:not(:nth-child(4)){border-right:1px solid var(--line)}
+}
+/* The side-by-side page has its own bar; the page breadcrumb would name only one pane. */
+body:has(#bus-view > .sbs) #breadcrumbs{display:none}
+html[data-organizations] .content:has(> #bus-view > .sbs) > .org-cue{margin:8px 14px}
+
+html[data-organizations] .pane-div{position:relative;background:var(--line);cursor:col-resize;touch-action:none;outline:none}
+html[data-organizations] .pane-div::before{content:"";position:absolute;inset:0 -4px;z-index:1}
+html[data-organizations] .pane-div:hover,html[data-organizations] .pane-div.dragging{background:var(--action)}
+html[data-organizations] .pane-div:focus-visible{background:var(--action);box-shadow:0 0 0 2px var(--action)}
+html[data-organizations] .pane-div[hidden]{display:none}
+
+@media (max-width:760px){
+  html[data-organizations] .content:has(> #bus-view > .sbs){padding:0}
+  html[data-organizations] .sbs{height:auto}
+  html[data-organizations] .sbs .ws-seg.pane-tabs{display:inline-flex}
+  html[data-organizations] .sbs .hide-m{display:none}
+  html[data-organizations] .panes,html[data-organizations] .panes.two{grid-template-columns:minmax(0,1fr)}
+  html[data-organizations] .pane.alt,html[data-organizations] .pane-div{display:none}
+  html[data-organizations] .pane-body{overflow:visible}
+  html[data-organizations] .pane-h{flex-wrap:wrap}
+  html[data-organizations] .pane-pick{flex:1 1 100%;max-width:none;order:5;margin-left:0}
+}
@@ -0,0 +1,477 @@
+// Side by side (U5, sample 07): two panes, each showing one page of any organization. A pane holds
+// the organization dashboard, the Agents levels or a project page (overview, conversations, tasks,
+// requirements, files), drawn by the same modules as the full view (workspace.js, projects.js) into
+// the pane instead of #bus-view. Every read names the pane's organization, so the panes never share
+// state. Pages that keep one global form, dialog or editor (a conversation, the room, settings, the
+// queue, docs, the inbox) are not offered in a pane; their links open the full view.
+//
+// The panes' routes, the divider and the phone's shown pane live in the URL
+// (#/orgs/<page>/side-by-side?a=<org>/<route>&b=<org>/<route>&w=<percent>&show=a|b), updated with
+// replaceState so nothing reloads, and the last layout is remembered in this browser.
+(() => {
+  'use strict';
+  if (!document.documentElement.hasAttribute('data-organizations')) return;
+  const data = window.MosaicWorkspaceData, ws = () => window.MosaicWorkspace;
+  const esc = value => String(value ?? '').replace(/[&<>"']/g, c => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' }[c]));
+  const enc = encodeURIComponent;
+  const STORE = 'mosaic-side-by-side-v1', POLL = 10000, LIST_TTL = 3000, PROJECTS_TTL = 30000;
+  const MIN = 25, MAX = 75, STEP = 5;
+  const ORG = /^[A-Za-z0-9][A-Za-z0-9._-]{0,63}$/;
+  const PROJECT = /^\/projects\/([A-Za-z0-9][A-Za-z0-9._-]{0,159})(?:\/(conversations|tasks|requirements|files))?$/;
+  const SECTIONS = { overview: 'Overview', conversations: 'Conversations', tasks: 'Tasks', requirements: 'Requirements', files: 'Files' };
+  const FOCUSABLE = 'a[href],button:not([disabled]),select,textarea,input,summary,[tabindex]:not([tabindex="-1"])';
+  const NAMES = { a: 'left', b: 'right' };
+  const load = () => { try { return localStorage.getItem(STORE); } catch { return null; } };
+  const save = value => { try { localStorage.setItem(STORE, value); } catch {} };
+  const paused = () => document.getElementById('pause')?.getAttribute('aria-pressed') === 'true';
+  const svg = d => `<svg class="i sm" viewBox="0 0 24 24" aria-hidden="true" focusable="false">${d}</svg>`;
+  const FULL = svg('<rect x="3.5" y="4.5" width="17" height="15" rx="1.5"/><path d="M12 4.5v15"/>');
+  const CLOSE = svg('<path d="M6 6l12 12M18 6 6 18"/>');
+  const PLUS = svg('<path d="M12 5v14M5 12h14"/>');
+
+  // A pane's page: the routes a pane can draw. Anything else is not pane-safe.
+  function page(route) {
+    if (route === '/organization') return { kind: 'dashboard' };
+    if (route === '/agents') return { kind: 'agents' };
+    const m = PROJECT.exec(route);
+    if (m && m[1] !== 'threads' && m[1] !== 'rooms') return { kind: 'project', id: m[1], section: m[2] || 'overview' };
+    return null;
+  }
+  // "<org>/<route>" from the URL; null when either part is not one a pane draws.
+  function parsePane(value) {
+    if (typeof value !== 'string') return null;
+    const cut = value.indexOf('/');
+    if (cut < 1) return null;
+    const org = value.slice(0, cut), route = value.slice(cut);
+    return ORG.test(org) && page(route) ? { org, route } : null;
+  }
+  const paneValue = p => `${p.org}${p.route}`;
+  const clampW = n => Math.min(MAX, Math.max(MIN, Math.round(n)));
+
+  // ---------- shared reads (one organization list and project lists for both panes) ----------
+  let listAt = 0, listPromise = null, projectReads = new Map();
+  function orgList(fresh = false) {
+    if (!listPromise || fresh || Date.now() - listAt > LIST_TTL) {
+      listAt = Date.now();
+      listPromise = Promise.all([data.organizations(), ws()?.themes?.()]).then(([rows]) => (Array.isArray(rows) ? rows : null)).catch(() => null);
+    }
+    return listPromise;
+  }
+  function projectsOf(org, fresh = false) {
+    const hit = projectReads.get(org);
+    if (hit && !fresh && Date.now() - hit.at < PROJECTS_TTL) return hit.promise;
+    const promise = data.projects(org).then(b => (Array.isArray(b?.rows) ? b.rows.filter(p => p && typeof p.id === 'string') : null)).catch(() => null);
+    projectReads.set(org, { at: Date.now(), promise });
+    return promise;
+  }
+
+  // ---------- state ----------
+  let mounted = null; // { root, panes: [pane], w, show, gen }
+  let mountGen = 0;
+  let listCache = null; // the last organization list read, for the shown-pane tabs
+
+  function readQuery(query) {
+    const q = new URLSearchParams(query || '');
+    return { a: parsePane(q.get('a')), b: parsePane(q.get('b')), w: Number(q.get('w')), show: q.get('show'), named: q.has('a') || q.has('b') };
+  }
+  function queryOf(state) {
+    const q = new URLSearchParams();
+    state.panes.forEach((p, i) => q.set(i ? 'b' : 'a', paneValue(p)));
+    q.set('w', String(state.w));
+    q.set('show', state.show);
+    return q.toString().replace(/%2F/g, '/');
+  }
+  function writeUrl() {
+    if (!mounted) return;
+    const qs = queryOf(mounted);
+    save(qs);
+    const next = `#/orgs/${enc(window.MosaicOrg.id)}/side-by-side?${qs}`;
+    if (location.hash !== next) history.replaceState(null, '', next);
+  }
+  // The first pane is this page's organization; the second is the next organization on the list,
+  // or this one's Agents when there is no other.
+  async function defaults() {
+    const here = window.MosaicOrg.id, list = await orgList();
+    const other = (list || []).find(o => o && !o.invalid && o.id !== here && ORG.test(o.id));
+    return [{ org: here, route: '/organization' }, other ? { org: other.id, route: '/organization' } : { org: here, route: '/agents' }];
+  }
+
+  // ---------- markup ----------
+  function paneShell(key) {
+    const name = NAMES[key];
+    return `<section class="pane" id="pane-${key}" data-pane="${key}" aria-label="${name[0].toUpperCase()}${name.slice(1)} pane">
+      <div class="pane-h ws-o" data-pane-head>
+        <span data-pane-av></span><span class="ttl" data-pane-ttl></span><span data-pane-state></span>
+        <label class="ws-sr" for="pane-${key}-pick">Page in the ${name} pane</label>
+        <select id="pane-${key}-pick" class="pane-pick" data-pane-pick></select>
+        <span class="tools"><a class="pane-tool" data-pane-full href="#" title="Open in full view"><span class="ws-sr" data-pane-full-label>Open in full view</span>${FULL}</a><button type="button" class="pane-tool" data-pane-close title="Close pane" aria-label="Close the ${name} pane">${CLOSE}</button></span>
+      </div>
+      <p class="pane-line" data-pane-line role="status"></p>
+      <div class="pane-body" data-pane-body tabindex="0" aria-label="${name[0].toUpperCase()}${name.slice(1)} pane content"></div>
+    </section>`;
+  }
+  function frame() {
+    return `<section class="sbs" data-side-by-side aria-labelledby="sbs-title">
+      <div class="panebar"><h1 id="sbs-title" tabindex="-1">Side by side</h1><span class="note" data-sbs-note></span>
+        <span class="ws-seg pane-tabs" role="group" aria-label="Shown pane" data-sbs-tabs></span>
+        <button type="button" class="ws-btn hide-m" data-pane-add>${PLUS}Add pane</button></div>
+      <div class="panes" data-sbs-panes>${paneShell('a')}<div class="pane-div" role="separator" tabindex="0" aria-orientation="vertical" aria-label="Resize panes" aria-controls="pane-a pane-b" aria-valuemin="${MIN}" aria-valuemax="${MAX}" data-sbs-divider></div>${paneShell('b')}</div>
+    </section>`;
+  }
+
+  // Orgs in the picker: every organization on the list. A pane draws a valid one's dashboard, Agents or
+  // any project the organization's project read lists; an invalid one is listed and cannot be chosen.
+  async function pickerHtml(p, list) {
+    const groups = await Promise.all((list || []).filter(o => o && ORG.test(o.id)).map(async org => {
+      const name = ws().label(org);
+      if (org.invalid) return `<optgroup label="${esc(name)} · invalid"><option disabled value="">Organization invalid</option></optgroup>`;
+      const rows = await projectsOf(org.id);
+      const opt = (route, text) => `<option value="${esc(`${org.id}${route}`)}">${esc(text)}</option>`;
+      const projects = rows === null ? '<option disabled value="">Projects unavailable</option>' : rows.filter(r => !r.archived && PROJECT.test(`/projects/${r.id}`)).map(r => opt(`/projects/${r.id}`, `Project: ${r.name || r.id}`)).join('');
+      return `<optgroup label="${esc(name)}${org.busHealthy ? '' : ' · bus unavailable'}">${opt('/organization', 'Dashboard')}${opt('/agents', 'Agents')}${projects}</optgroup>`;
+    }));
+    let html = groups.join('');
+    const value = paneValue(p);
+    // A project section, or a page the list no longer names, is still the pane's page: keep it selectable.
+    if (!html.includes(`value="${esc(value)}"`)) html = `<option value="${esc(value)}">${esc(p.title || value)}</option>${html}`;
+    return html;
+  }
+
+  // ---------- drawing one pane ----------
+  const els = p => ({
+    head: p.el.querySelector('[data-pane-head]'), av: p.el.querySelector('[data-pane-av]'), ttl: p.el.querySelector('[data-pane-ttl]'),
+    state: p.el.querySelector('[data-pane-state]'), pick: p.el.querySelector('[data-pane-pick]'), full: p.el.querySelector('[data-pane-full]'),
+    fullLabel: p.el.querySelector('[data-pane-full-label]'), close: p.el.querySelector('[data-pane-close]'), line: p.el.querySelector('[data-pane-line]'), body: p.el.querySelector('[data-pane-body]'),
+  });
+  const setHtml = (el, html) => { if (el && el.innerHTML !== html) el.innerHTML = html; };
+  const setText = (el, text) => { if (el && el.textContent !== text) el.textContent = text; };
+
+  // Links a page draws are relative to the page's organization. In a pane they name the pane's
+  // organization; reads the page links to (/api/...) name it too.
+  function rewrite(p, root) {
+    const prefix = `#/orgs/${enc(p.org)}`;
+    for (const a of root.querySelectorAll('a[href^="#/"]')) if (!a.getAttribute('href').startsWith('#/orgs/')) a.setAttribute('href', prefix + a.getAttribute('href').slice(1));
+    for (const a of root.querySelectorAll('a[href^="/api/"]')) if (!a.getAttribute('href').startsWith('/api/orgs/')) a.setAttribute('href', `/api/orgs/${enc(p.org)}/${a.getAttribute('href').slice(5)}`);
+    // The pane's title is the page's heading; the side-by-side page keeps the one level-1 heading.
+    for (const h of root.querySelectorAll('h1:not([aria-level])')) h.setAttribute('aria-level', '2');
+  }
+  // Focus and scroll survive a repaint of this pane only. Focus in the other pane is never taken.
+  function capture(p, root) {
+    const a = document.activeElement, inside = !!a && a !== root && root.contains(a);
+    return {
+      top: root.scrollTop,
+      focus: inside ? { key: a.dataset?.focusKey || null, href: a.getAttribute('href'), index: [...root.querySelectorAll(FOCUSABLE)].indexOf(a), h1: a.tagName === 'H1' } : null,
+    };
+  }
+  function restore(p, root, kept) {
+    root.scrollTop = kept.top;
+    const f = kept.focus, a = document.activeElement;
+    if (!f || (a && a !== document.body && !root.contains(a))) return;
+    const target = (f.key && root.querySelector(`[data-focus-key="${CSS.escape(f.key)}"]`))
+      || (f.href && [...root.querySelectorAll('a[href]')].find(x => x.getAttribute('href') === f.href))
+      || (f.h1 && root.querySelector('h1'))
+      || root.querySelectorAll(FOCUSABLE)[f.index];
+    (target || root).focus({ preventScroll: true });
+  }
+  function paintBody(p, html) {
+    const { body } = els(p);
+    if (p.html === html && body.childElementCount) return;
+    const kept = capture(p, body);
+    body.innerHTML = html; p.html = html; p.project = null;
+    rewrite(p, body);
+    restore(p, body, kept);
+  }
+
+  // A focus move that finishes after an asynchronous read happens only if the viewer has not
+  // moved on: focus is still where it was when the action started, nowhere, or inside this pane.
+  function mayFocus(p, before) {
+    const a = document.activeElement;
+    return !a || a === document.body || a === before || p.el.contains(a);
+  }
+  async function drawPane(p, { fresh = false, focusHead = false } = {}) {
+    if (!mounted || !p.el.isConnected) return;
+    const before = document.activeElement;
+    const turn = ++p.turn, gen = mountGen, live = () => mounted && gen === mountGen && turn === p.turn && p.el.isConnected;
+    clearTimeout(p.timer);
+    const e = els(p), what = page(p.route);
+    const list = await orgList(fresh);
+    if (!live()) return;
+    if (list) listCache = list;
+    const org = list?.find(o => o?.id === p.org) || null;
+    const name = org ? ws().label(org) : p.org;
+    // Header: the organization's mark, the page's title, its state, the picker and the tools.
+    if (org) e.head.setAttribute('style', ws().colours(org)); else e.head.removeAttribute('style');
+    setHtml(e.av, org ? ws().av(org, 'md') : '<span class="ws-av md" aria-hidden="true">?</span>');
+    const [scls, sglyph, sword] = org ? ws().state(org) : ['s-unknown', '?', 'not on your list'];
+    setHtml(e.state, org?.busHealthy && !org.invalid ? '' : ws().dot(scls, sglyph, sword, true));
+    const fullHref = `#/orgs/${enc(p.org)}${p.route}`;
+    if (e.full.getAttribute('href') !== fullHref) e.full.setAttribute('href', fullHref);
+
+    let line = '', html = null;
+    if (!list) line = 'The organization list could not be read. This pane shows what its own reads return.';
+    else if (!org) { line = `${p.org} is not on your organization list.`; html = '<p class="ws-line">Nothing is read for an organization that is not on your list.</p>'; }
+    else if (org.invalid) { line = `${name}: organization invalid${org.reason ? ` (${org.reason})` : ''}.`; html = '<p class="ws-line">Nothing is read from an invalid organization. Fix its file under Settings, Organizations.</p>'; }
+    else if (!org.busHealthy) line = `${name}: bus unavailable. Reads from this organization may fail; the other pane is not affected.`;
+    setText(e.line, line); e.line.hidden = !line;
+
+    let title = what?.kind === 'agents' ? 'Agents' : 'Dashboard';
+    if (html === null && what?.kind === 'dashboard') html = await ws().dashboard(p.org, { pane: true, idPrefix: `pane-${p.key}-` }).catch(() => '<p class="ws-line">Dashboard unavailable.</p>');
+    else if (html === null && what?.kind === 'agents') html = await ws().agentGrid('', p.org).catch(() => '<p class="ws-line">Agents unavailable.</p>');
+    if (!live()) return;
+    if (html === null && what?.kind === 'project') {
+      title = await drawProject(p, e, what, fresh, live);
+      if (title === null || !live()) return;
+    } else if (html !== null) paintBody(p, html);
+    p.title = title;
+    setHtml(e.ttl, `${esc(title)}<small>${esc(name)}</small>`);
+    p.el.setAttribute('aria-label', `${NAMES[p.key][0].toUpperCase()}${NAMES[p.key].slice(1)} pane: ${title}, ${name}`);
+    setText(e.fullLabel, `Open ${title}, ${name}, in full view`);
+    // The picker is rebuilt only while it is closed and unfocused, so a choice in progress stays.
+    if (document.activeElement !== e.pick) {
+      const options = await pickerHtml(p, list);
+      if (!live()) return;
+      if (document.activeElement !== e.pick) { setHtml(e.pick, options); e.pick.value = paneValue(p); }
+    }
+    paintBar(); fit();
+    if (focusHead && mayFocus(p, before)) (e.body.querySelector('h1') || e.body).focus({ preventScroll: true });
+    p.timer = setTimeout(() => tick(p), POLL);
+  }
+  function tick(p) {
+    if (!mounted || !p.el.isConnected) return;
+    if (paused()) { p.timer = setTimeout(() => tick(p), POLL); return; }
+    void drawPane(p);
+  }
+
+  // A project page: projects.js's header and content, mounted into the pane with the pane's
+  // organization, read-only (a pane never sends).
+  // Every write below happens only while this draw is still the pane's current one (live()), so a
+  // slow read never paints an old page or organization over the one the viewer has since chosen.
+  async function drawProject(p, e, what, fresh, live) {
+    const org = p.org;
+    const [projects, threadsRead] = await Promise.all([projectsOf(org, fresh), data.threads(org).catch(() => null)]);
+    if (!live() || p.org !== org) return null;
+    const project = projects?.find(r => r.id === what.id);
+    const sectionName = SECTIONS[what.section];
+    if (!project) {
+      paintBody(p, projects === null ? '<p class="ws-line">Projects unavailable. The organization did not answer the project read.</p>' : '<p class="ws-line">This project is not in the organization\'s project list.</p>');
+      return what.id;
+    }
+    const threads = Array.isArray(threadsRead?.rows) ? threadsRead.rows : [];
+    const head = window.MosaicProjects.header(project, what.section, threads);
+    const conv = what.section === 'conversations' ? conversations(project, threads, threadsRead) : null;
+    const key = JSON.stringify([org, project.id, what.section, head, conv]);
+    const { body } = e;
+    if (p.project?.key !== key) {
+      const kept = capture(p, body);
+      body.innerHTML = `<div class="chat-area pane-project">${head}${conv ?? '<div data-project-content>Reading…</div>'}</div>`;
+      p.html = null; p.project = { key };
+      rewrite(p, body);
+      restore(p, body, kept);
+    }
+    const content = body.querySelector('[data-project-content]');
+    if (content) await window.MosaicProjects.mountContent({ container: content, project, threads, section: what.section, canSend: false, org, pane: true, views: viewsOf(p, org) });
+    return what.section === 'overview' ? project.name || project.id : `${project.name || project.id} · ${sectionName}`;
+  }
+  // A pane's request choice and PRD disclosure, per organization, kept on the pane so a repaint
+  // that replaces the project content keeps them.
+  function viewsOf(p, org) {
+    if (!p.views.has(org)) p.views.set(org, { selected: new Map(), expanded: new Set() });
+    return p.views.get(org);
+  }
+  function conversations(project, threads, read) {
+    if (!read) return '<p class="ws-line">Conversations unavailable.</p>';
+    const own = threads.filter(t => t && !t.shared && t.project === project.id && typeof t.id === 'string');
+    const rows = own.map(t => `<a class="project-conversation-row" href="#/projects/threads/${enc(t.id)}" data-focus-key="${esc(`conv:${t.id}`)}"><span class="project-conversation-icon" aria-hidden="true">◌</span><span><strong>${esc(t.name || t.id)}</strong><small>With ${esc(t.instance || 'no agent recorded')}</small></span><span aria-hidden="true">›</span></a>`).join('');
+    return `<div class="project-section-title"><h2>Conversations</h2></div><div data-project-conversations>${rows || '<p>No conversations yet.</p>'}</div><p class="ws-line">A conversation opens in its full view.</p>`;
+  }
+
+  // ---------- the bar, tabs, divider and layout ----------
+  function paintBar() {
+    if (!mounted) return;
+    const { root, panes, show } = mounted, two = panes.length === 2;
+    setText(root.querySelector('[data-sbs-note]'), `${panes.length} ${panes.length === 1 ? 'pane' : 'panes'} · each pane reads its own organization's bus and keeps its own state`);
+    const tabs = root.querySelector('[data-sbs-tabs]'), focusedTab = tabs.contains(document.activeElement) ? document.activeElement.dataset.paneShow : null;
+    const list = listCache;
+    const html = panes.map(p => {
+      const org = list?.find(o => o?.id === p.org);
+      return `<button type="button" data-pane-show="${p.key}" aria-pressed="${show === p.key}" aria-controls="pane-${p.key}">${org ? ws().av(org, 'xs') : ''}<span>${esc(p.title || 'Reading…')}</span></button>`;
+    }).join('');
+    if (tabs.innerHTML !== html) { tabs.innerHTML = html; if (focusedTab) tabs.querySelector(`[data-pane-show="${focusedTab}"]`)?.focus({ preventScroll: true }); }
+    const add = root.querySelector('[data-pane-add]');
+    add.disabled = two; add.title = two ? 'Side by side holds two panes. Close one to choose another.' : 'Open a second pane';
+    for (const p of panes) { const c = p.el.querySelector('[data-pane-close]'); c.hidden = !two; }
+  }
+  function layout() {
+    if (!mounted) return;
+    const { root, panes, w, show } = mounted, two = panes.length === 2;
+    const box = root.querySelector('[data-sbs-panes]'), divider = root.querySelector('[data-sbs-divider]');
+    box.classList.toggle('two', two);
+    box.style.setProperty('--sbs-a', `${w}fr`); box.style.setProperty('--sbs-b', `${100 - w}fr`);
+    divider.hidden = !two;
+    divider.setAttribute('aria-valuenow', String(w));
+    divider.setAttribute('aria-valuetext', `Left pane ${w} percent, right pane ${100 - w} percent`);
+    root.querySelector('#pane-b').hidden = !two;
+    for (const p of panes) p.el.classList.toggle('alt', show !== p.key);
+    fit();
+  }
+  // Wide screens: the panes fill the window below the bar and each scrolls on its own.
+  const wide = window.matchMedia('(min-width: 761px)');
+  function fit() {
+    if (!mounted) return;
+    const { root } = mounted;
+    if (!wide.matches) { root.style.height = ''; return; }
+    const foot = document.querySelector('body > .foot, .foot')?.getBoundingClientRect().height || 0;
+    const top = root.getBoundingClientRect().top;
+    root.style.height = `${Math.max(360, Math.floor(window.innerHeight - Math.max(top, 0) - foot))}px`;
+  }
+  function setWidth(w, persist = true) {
+    if (!mounted) return;
+    const next = clampW(w);
+    if (next === mounted.w) return;
+    mounted.w = next; layout(); if (persist) writeUrl();
+  }
+
+  // ---------- events (bound once to the mount root) ----------
+  function bind(root) {
+    const divider = root.querySelector('[data-sbs-divider]');
+    divider.addEventListener('keydown', e => {
+      const w = mounted?.w; if (w === undefined) return;
+      const next = { ArrowLeft: w - STEP, ArrowDown: w - STEP, ArrowRight: w + STEP, ArrowUp: w + STEP, PageDown: w - 10, PageUp: w + 10, Home: MIN, End: MAX }[e.key];
+      if (next === undefined) return;
+      e.preventDefault(); setWidth(next);
+    });
+    divider.addEventListener('pointerdown', e => {
+      if (e.button !== 0) return;
+      e.preventDefault(); divider.focus({ preventScroll: true }); divider.setPointerCapture(e.pointerId); divider.classList.add('dragging');
+      const box = root.querySelector('[data-sbs-panes]').getBoundingClientRect();
+      const move = ev => setWidth(((ev.clientX - box.left) / box.width) * 100, false);
+      const up = () => { divider.removeEventListener('pointermove', move); divider.removeEventListener('pointerup', up); divider.removeEventListener('pointercancel', up); divider.classList.remove('dragging'); writeUrl(); };
+      divider.addEventListener('pointermove', move); divider.addEventListener('pointerup', up); divider.addEventListener('pointercancel', up);
+    });
+    root.addEventListener('change', e => {
+      const pick = e.target.closest?.('[data-pane-pick]'); if (!pick || !mounted) return;
+      const p = mounted.panes.find(x => x.el.contains(pick)), next = parsePane(pick.value);
+      if (!p || !next) return;
+      go(p, next, false);
+    });
+    root.addEventListener('click', e => {
+      if (!mounted) return;
+      const show = e.target.closest?.('[data-pane-show]');
+      if (show) { mounted.show = show.dataset.paneShow === 'b' && mounted.panes.length === 2 ? 'b' : 'a'; layout(); paintBar(); writeUrl(); return; }
+      if (e.target.closest?.('[data-pane-add]')) { void addPane(); return; }
+      const close = e.target.closest?.('[data-pane-close]');
+      if (close) { closePane(mounted.panes.find(x => x.el.contains(close))); return; }
+      // A plain click on a link to a page a pane draws, in the pane's own organization, opens it in
+      // the pane. Anything else (another organization, a page a pane does not draw, a new tab) is
+      // an ordinary link to the full view.
+      const a = e.target.closest?.('a[href^="#/orgs/"]');
+      if (!a || a.hasAttribute('data-pane-full') || e.defaultPrevented || e.button !== 0 || e.metaKey || e.ctrlKey || e.shiftKey || e.altKey) return;
+      const p = mounted.panes.find(x => x.el.contains(a)); if (!p) return;
+      const m = /^#\/orgs\/([^/?#]+)(\/[^?#]*)$/.exec(a.getAttribute('href'));
+      let org, route;
+      try { org = decodeURIComponent(m?.[1] ?? ''); route = decodeURIComponent(m?.[2] ?? ''); } catch { return; }
+      if (org !== p.org || !page(route)) return;
+      e.preventDefault();
+      go(p, { org, route }, true);
+    });
+  }
+  function go(p, next, focusHead) {
+    p.org = next.org; p.route = next.route; p.html = null; p.project = null; p.title = null;
+    els(p).body.scrollTop = 0;
+    writeUrl();
+    void drawPane(p, { focusHead });
+  }
+  async function addPane() {
+    if (!mounted || mounted.panes.length !== 1) return;
+    const before = document.activeElement;
+    const [a] = mounted.panes, list = await orgList();
+    if (!mounted || mounted.panes.length !== 1) return;
+    const other = (list || []).find(o => o && !o.invalid && o.id !== a.org && ORG.test(o.id));
+    const b = makePane('b', other ? { org: other.id, route: '/organization' } : { org: a.org, route: a.route === '/agents' ? '/organization' : '/agents' });
+    mounted.panes.push(b); mounted.show = 'b';
+    layout(); paintBar(); writeUrl();
+    await drawPane(b);
+    if (mounted?.panes.includes(b) && mayFocus(b, before)) els(b).pick.focus({ preventScroll: true });
+  }
+  function closePane(p) {
+    if (!mounted || !p || mounted.panes.length !== 2) return;
+    clearTimeout(p.timer); p.turn++;
+    const keep = mounted.panes.find(x => x !== p);
+    // The remaining pane becomes the first: its page moves into pane a's element.
+    const a = mounted.panes[0];
+    if (keep !== a) {
+      const b = mounted.panes[1];
+      clearTimeout(b.timer); b.turn++;
+      a.org = keep.org; a.route = keep.route; a.html = null; a.project = null; a.title = keep.title; a.views = keep.views;
+    }
+    setHtml(els(mounted.panes[1]).body, ''); mounted.panes[1].html = null; mounted.panes[1].project = null;
+    mounted.panes = [a]; mounted.show = 'a';
+    layout(); paintBar(); writeUrl();
+    // The close button just left the page; focus goes to the remaining pane's picker now, and again
+    // after its draw only if the viewer has not moved elsewhere meanwhile.
+    els(a).pick.focus({ preventScroll: true });
+    const before = document.activeElement;
+    void drawPane(a).then(() => { if (mounted?.panes[0] === a && mayFocus(a, before)) els(a).pick.focus({ preventScroll: true }); });
+  }
+  function makePane(key, at) {
+    const el = mounted.root.querySelector(`#pane-${key}`);
+    return { key, el, org: at.org, route: at.route, turn: 0, timer: null, html: null, project: null, title: null, views: new Map() };
+  }
+
+  // ---------- public ----------
+  async function mount(container, query, { navigated = false } = {}) {
+    unmount();
+    const gen = ++mountGen;
+    container.innerHTML = frame();
+    const root = container.querySelector('[data-side-by-side]');
+    mounted = { root, panes: [], w: 50, show: 'a', gen, observers: [] };
+    // projects.js paints a project's content after its own reads; its links are rewritten as they
+    // land. One observer per pane element for the life of the mount, applying whichever pane object
+    // holds that element now, so a closed and re-added pane never runs an old organization's rewrite.
+    const m = mounted;
+    for (const key of ['a', 'b']) {
+      const body = root.querySelector(`#pane-${key} [data-pane-body]`);
+      const observer = new MutationObserver(() => {
+        if (mounted !== m) return;
+        const p = m.panes.find(x => x.key === key);
+        if (p) rewrite(p, body);
+      });
+      observer.observe(body, { childList: true, subtree: true });
+      m.observers.push(observer);
+    }
+    bind(root);
+    window.addEventListener('resize', fit);
+    document.title = 'Side by side · Mosaic Console';
+    if (navigated) root.querySelector('h1').focus({ preventScroll: true });
+    let wanted = readQuery(query);
+    if (!wanted.named) { const kept = readQuery(load() || ''); if (kept.a) wanted = { ...kept, named: true }; }
+    let at = [wanted.a, wanted.b].filter(Boolean);
+    if (!at.length) at = await defaults();
+    if (!mounted || gen !== mountGen) return;
+    listCache = await orgList();
+    if (!mounted || gen !== mountGen) return;
+    mounted.panes = at.slice(0, 2).map((x, i) => makePane(i ? 'b' : 'a', x));
+    mounted.w = Number.isFinite(wanted.w) && wanted.w ? clampW(wanted.w) : 50;
+    mounted.show = wanted.show === 'b' && mounted.panes.length === 2 ? 'b' : 'a';
+    layout(); paintBar(); writeUrl();
+    await Promise.all(mounted.panes.map(p => drawPane(p)));
+  }
+  function unmount() {
+    if (!mounted) return;
+    for (const p of mounted.panes) { clearTimeout(p.timer); p.turn++; }
+    for (const o of mounted.observers) o.disconnect();
+    window.removeEventListener('resize', fit);
+    mounted = null; mountGen++;
+  }
+  // The Console's Refresh: both panes read again now, each keeping its own focus and scroll.
+  function refresh() {
+    if (!mounted) return;
+    projectReads = new Map();
+    void orgList(true).then(rows => { if (rows) listCache = rows; });
+    for (const p of mounted.panes) void drawPane(p, { fresh: true });
+  }
+  // The list the tabs draw from follows each fresh read of the organization list.
+  document.addEventListener('mosaic-org-list', e => { if (Array.isArray(e.detail?.rows)) listCache = e.detail.rows; });
+
+  window.MosaicPanes = Object.freeze({ mount, unmount, refresh, page });
+})();
@@ -31,12 +31,15 @@
  let treeRows=[], treeThreads=[], treeGeneration=0, treeState, treeRead=null, treeReadAt=0;
  const treeFocus = new WeakMap();
  try { treeState=JSON.parse(localStorage.getItem(storageKey) || '{}'); if (!treeState || Array.isArray(treeState) || typeof treeState !== 'object') treeState={}; } catch { treeState={}; }
+  // A side-by-side pane reads its own organization: its reads name that organization explicitly.
+  const at=(org,url)=>org && url.startsWith('/api/') ? `/api/orgs/${encodeURIComponent(org)}/${url.slice(5)}` : url;
  async function read(url) {
    const response=await fetch(url,{cache:'no-store',redirect:'manual'});
    if(response.status===401 || response.type==='opaqueredirect') { document.dispatchEvent(new CustomEvent('mosaic-signed-out',{detail:{signIn:true}})); throw Error('signed-out'); }
    if(!response.ok) { const body=await response.json().catch(()=>null); const error=Error('unavailable'); error.status=response.status; error.code=body?.error; throw error; }
    return response.json();
  }
+  const readAt=url=>read(url);
  function currentProject(route) {
    const id=route.match(/^\/(?:projects|chat)\/(?:projects\/|rooms\/)?([0-9a-f-]{36})/i)?.[1];
    if(id) return id;
@@ -104,8 +107,9 @@
  const same=(a,b)=>JSON.stringify(canonical(a))===JSON.stringify(canonical(b));
  const material=(d,s)=>d && d.candidate && s?.candidate && same(d.candidate,s.candidate) && d.candidate.request===s.request && d.candidate.project===s.project && d.candidate.mode_revision===s.mode_revision && typeof d.prd==='string' && Array.isArray(d.requirements) && Array.isArray(d.candidate.requirements) && d.requirements.length===d.candidate.requirements.length && d.requirements.every((r,i)=>r && r.id===d.candidate.requirements[i]?.id && r.title===d.candidate.requirements[i]?.title && typeof r.text==='string') && d.snapshot && Number.isSafeInteger(d.snapshot.revision) && d.snapshot.revision>=0 && d.snapshot.id===s.snapshot && (d.snapshot.id===null || requestId(d.snapshot.id) && d.snapshot.revision>0);
  const ownThreads=(project,threads)=>threads.filter(t=>t.project===project.id && !t.shared && UUID.test(t.id));
-  async function gather(project,threads) {
-    const own=ownThreads(project,threads), key=project.id+':'+String(project.repo)+':'+own.map(t=>t.id).join(',');
+  async function gather(project,threads,org=null) {
+    const read=url=>readAt(at(org,url));
+    const own=ownThreads(project,threads), key=(org?org+'|':'')+project.id+':'+String(project.repo)+':'+own.map(t=>t.id).join(',');
    const prior=cache.get(key); if(prior && Date.now()-prior.at<10000) return prior.promise;
    const started=epoch;
    const promise=(async()=>{
@@ -133,7 +137,7 @@
        const [draft,workspace]=await Promise.all([read(base+'/draft').catch(()=>null),read(base+'/workspace').catch(()=>null)]);
        return {...item,state,draft:material(draft,state)?draft:null,materialFailed:!!state.candidate && !material(draft,state),workspace};
      }))).filter(Boolean);
-      const [tasks,catalog,room]=await Promise.all([read('/api/bus/tasks').catch(()=>null),read('/api/chat/instances').catch(()=>null),readRoomStatus(project)]);
+      const [tasks,catalog,room]=await Promise.all([read('/api/bus/tasks').catch(()=>null),read('/api/chat/instances').catch(()=>null),readRoomStatus(project,org)]);
      const members=Array.isArray(catalog?.rows)?catalog.rows.filter(m=>typeof m?.instance==='string' && own.some(t=>t.instance===m.instance && t.name===t.instance)).length:null;
      let docs=project.repo ? null : {files:[]}, north=null, recordsMissing=false, northMissing=false, northRecordsMissing=false;
      if(project.repo && /^[A-Za-z0-9][A-Za-z0-9._/-]{0,200}$/.test(project.repo)) {
@@ -145,9 +149,9 @@
    })();
    cache.set(key,{at:Date.now(),promise}); return promise;
  }
-  async function readRoomStatus(project) {
+  async function readRoomStatus(project,org=null) {
    try {
-      const response=await fetch(`/api/chat/rooms/${encodeURIComponent(project.id)}/messages?limit=100`,{cache:'no-store',redirect:'manual'});
+      const response=await fetch(at(org,'/api/chat/rooms/')+`${encodeURIComponent(project.id)}/messages?limit=100`,{cache:'no-store',redirect:'manual'});
      if(response.status===401 || response.type==='opaqueredirect') { document.dispatchEvent(new CustomEvent('mosaic-signed-out',{detail:{signIn:true}})); return 'Unavailable'; }
      const body=await response.json();
      if(response.ok && Array.isArray(body?.rows) && typeof body.hasMore==='boolean') return 'Open';
@@ -194,11 +198,18 @@
    return `<h2>Reviewed deliveries <span class="project-count">${f.reviewed.length}</span></h2>${f.reviewed.length?f.reviewed.map(({r,file})=>`<div class="project-panel"><span class="project-delivery-icon" aria-hidden="true">▤</span><strong>${clean(file.name)}</strong> <span class="project-chip success">Reviewed</span><p>Request ${clean(r.id)} · from ${clean(r.thread.name)} · Reviewed delivery. Not landed or deployed.</p><div class="project-delivery-actions"><a class="btn" target="_blank" rel="noopener noreferrer" href="/api/requests/${encodeURIComponent(r.id)}/artifact/${encodeURIComponent(file.id)}/text">Open as text</a> <a class="btn" download href="/api/requests/${encodeURIComponent(r.id)}/artifact/${encodeURIComponent(file.id)}">Download</a>${deliveryPr(r)?` <a class="btn" target="_blank" rel="noopener noreferrer" href="${esc(deliveryPr(r))}">Open pull request</a>`:''}</div><p>Open shows plain text in a new tab. Downloaded HTML can be opened locally after saving.</p></div>`).join(''):`<p>${data.disabled?'Files are unavailable.':data.failed?'Reviewed files are unavailable.':data.requests.length?'No reviewed file is available.':'No request files yet. Files appear when a request in this project produces them.'}</p>`}<h2>Draft workspace <span class="project-count">${f.drafts.length}</span></h2><p>Names only. Draft files may change and are not reviewed deliveries.</p><div class="project-panel project-file-list">${f.drafts.length?f.drafts.map(({r,name})=>`<div><span><span aria-hidden="true">▤</span> <code>${clean(name)}</code></span><span>Request ${clean(r.id)} · <span class="project-chip">Draft</span></span></div>`).join(''):data.failed || data.requests.some(r=>r.workspace?.available!==true || !Array.isArray(r.workspace.entries))?'<p>Could not read draft workspace. Try again later.</p>':'<p>No draft files found.</p>'}${data.requests.some(r=>r.workspace?.truncated)?'<p>The draft list was truncated.</p>':''}</div><h2>Project documents ${docs?`<span class="project-count">${docs.length}</span>`:''}</h2><div class="project-panel project-file-list">${!project.repo?'No linked repository.':data.recordsMissing?window.MosaicRecords.markup(project.repo):!docs?'Project documents unavailable. Docs could not read this project’s repository.':docs.length?docs.map(name=>`<div><span><span aria-hidden="true">▤</span> <code>${clean(name)}</code></span><a href="#/docs/${encodeURIComponent(project.repo)}/${encodeURIComponent(name)}">Open in Docs</a></div>`).join(''):'No project documents found.'}</div>`;
  }
  const expandedPrds = new Set();
-  function requirementView(data,project,selected) {
+  // U5: a project in a Side by side pane keeps its own request choice and PRD disclosure, so two
+  // panes showing the same project (or two organizations' projects with one id) never share them.
+  // The pane passes `views`, kept on the pane per organization, so the state outlives a repaint
+  // that replaces the content element (a new conversation changes the header). Without it, the
+  // state lives as long as the container.
+  const paneViews = new WeakMap();
+  const viewState=(container,pane,views)=>{if(!pane) return {selected:selectedRequests,expanded:expandedPrds}; if(views?.selected instanceof Map && views.expanded instanceof Set) return views; if(!paneViews.has(container)) paneViews.set(container,{selected:new Map(),expanded:new Set()}); return paneViews.get(container);};
+  function requirementView(data,project,selected,expandedSet=expandedPrds) {
    const options=data.requests.filter(r=>r.draft), r=options.find(x=>x.id===selected)||options[0], d=r?.draft;
    const north=typeof data.north?.content==='string'?data.north.content:null;
    const select=options.length>1?`<label>Request <select id="project-request-select">${options.map(x=>`<option value="${clean(x.id)}"${x===r?' selected':''}>${clean(x.id)} · ${clean(x.thread.name)}</option>`).join('')}</select></label>`:'';
-    const candidate=d?.candidate, expanded=r && expandedPrds.has(project.id+':'+r.id);
+    const candidate=d?.candidate, expanded=r && expandedSet.has(project.id+':'+r.id);
    const docPath=candidate?.prd_path, docLink=project.repo && typeof docPath==='string' && /^docs\/[A-Za-z0-9][A-Za-z0-9._-]{0,127}\.md$/.test(docPath) ? `#/docs/${encodeURIComponent(project.repo)}/${encodeURIComponent(docPath)}` : null;
    const rows=candidate ? [['PRD version',candidate.prd_version],['Approved snapshot',d.snapshot.id || 'None'],['PRD file',docPath],['PRD blob',candidate.prd_blob],['Records commit',candidate.records_commit],['Confirmed intent commit',candidate.spec_commit],['Mode revision',candidate.mode_revision]].map(([label,value])=>`<div class="project-provenance-row"><span>${label}</span>${label==='PRD file' && docLink?`<a href="${docLink}"><code>${clean(value)}</code></a>`:`<code>${clean(value)}</code>`}</div>`).join('') : '<p>Unavailable until a PRD is read.</p>';
    return `${r?`<div class="project-panel project-source">${select || `Request <code>${clean(r.id)}</code>`} · ${chip(r.state)} · from ${clean(r.thread.name)} <a href="${conversationLink(r.thread)}">Open conversation</a></div>`:select}<div class="project-columns"><section><h2>Project direction</h2><h3 id="project-north-star">North star</h3>${north!==null?`<div data-north-star></div><a class="project-text-link" href="#/docs/${encodeURIComponent(project.repo)}/${encodeURIComponent('spec/north-star.md')}">Open north star in Docs</a>`:data.northRecordsMissing?`<p>${window.MosaicRecords.markup(project.repo)}</p>`:data.northMissing?'<p>No north star yet.</p>':project.repo?'<p>North star unavailable. Docs could not read this project’s repository.</p>':`<p>This project has no linked repository. The north star and project documents live in a repository. Linking one to an existing project isn't available yet.</p>`}<h3 id="project-prd">${candidate?`PRD ${clean(candidate.prd_version)}`:'PRD'} ${candidate?`<span class="project-chip ${d.snapshot.id?'success':''}">${d.snapshot.id?'Approved':'Draft'}</span>`:''}</h3>${d?`<p>${d.snapshot.id?'Approved snapshot '+clean(d.snapshot.id):'This candidate has no active approved snapshot.'}</p><div class="project-panel project-prd-panel"><div class="project-prd-preview${expanded?' expanded':''}" data-prd></div><button type="button" class="btn project-prd-toggle" aria-expanded="${!!expanded}">${expanded?'Show less':'Show full PRD'}</button></div><h3>Requirements <span class="project-count">${d.requirements.length}</span></h3><div class="project-panel">${d.requirements.map((req,i)=>`<details data-restore-key="req:${clean(r.id)}:${clean(req.id)}"><summary>${clean(req.id)} · ${clean(req.title)}</summary><p>${clean(req.text)}</p><p>Requirement identity: <code>${clean(candidate.requirements[i]?.path)}</code> · <code>${clean(candidate.requirements[i]?.blob)}</code></p></details>`).join('')}</div>`:`<p>${(data.failed || data.requests.some(x=>x.materialFailed))?'Request or PRD unavailable. Refresh to try again.':'No current PRD candidate or approved snapshot. Waiting for a PRD submission.'}</p>`}${d && data.requests.some(x=>x.materialFailed)?'<p role="status">Some request PRDs could not be read. Refresh to try again.</p>':''}</section><aside class="project-panel project-provenance"><details data-restore-key="provenance"${matchMedia('(min-width:700px)').matches?' open':''}><summary>Version and provenance</summary>${rows}${candidate?`<p>Approval and revocation live in the conversation's Request details.</p><a href="${conversationLink(r.thread)}">Open conversation</a>`:''}</details></aside></div>`;
@@ -241,31 +252,32 @@
    const wanted=new Set((restore.disclosures || []).map(String)), closed=new Set((restore.closed || []).map(String));
    [...root.querySelectorAll('details')].forEach((el,i)=>{const key=restoreKey(el,i);if(wanted.has(key)) el.open=true;else if(el.dataset.restoreKey && closed.has(key)) el.open=false;});
    const f=restore.projectFocus; if(!f) return;
-    const focus=f.id ? document.getElementById(f.id) : f.details ? [...root.querySelectorAll('details[data-restore-key]')].find(el=>el.dataset.restoreKey===f.details)?.querySelector(':scope > summary') : root.querySelectorAll(FOCUSABLE)[f.index];
+    const focus=f.id ? root.querySelector('#'+CSS.escape(f.id)) : f.details ? [...root.querySelectorAll('details[data-restore-key]')].find(el=>el.dataset.restoreKey===f.details)?.querySelector(':scope > summary') : root.querySelectorAll(FOCUSABLE)[f.index];
    focus?.focus({preventScroll:true});
  }
-  async function mountContent({container,project,threads,section,canSend,restore,roomReceipt}) {
+  async function mountContent({container,project,threads,section,canSend,restore,roomReceipt,org=null,pane=false,views:paneState=null}) {
    if(!container || !project) return;
    const generation=epoch, run=(contentRuns.get(container) || 0)+1;
    contentRuns.set(container,run);
    if (!contentPaints.has(container)) container.textContent='Reading…';
-    const data=await gather(project,threads).catch(()=>null);
+    const data=await gather(project,threads,org).catch(()=>null);
    if(!container.isConnected || generation!==epoch || contentRuns.get(container)!==run || document.body.classList.contains('signed-out')) return;
    if(!data){contentPaints.delete(container);container.textContent='Project data unavailable. Refresh to try again.';return;}
+    const views=viewState(container,pane,paneState), selectedRequests=views.selected, expandedPrds=views.expanded;
    const selected=selectedRequests.get(project.id);
    if(selected && !data.requests.some(r=>r.id===selected && r.draft)) selectedRequests.delete(project.id);
    const selection=selectedRequests.get(project.id);
-    const view = section==='requirements'?requirementView(data,project,selection):section==='files'?filesView(data,project):section==='tasks'?tasksView(data):overview(data,project,canSend,roomReceipt);
+    const view = section==='requirements'?requirementView(data,project,selection,expandedPrds):section==='files'?filesView(data,project):section==='tasks'?tasksView(data):overview(data,project,canSend,roomReceipt);
    const selectedRequest=data.requests.find(r=>r.id===(selection||data.requests.find(x=>x.draft)?.id));
    // The generated presentation and separately mounted Markdown determine visible content.
    const signature=JSON.stringify([view, section==='requirements' ? selectedRequest?.draft?.prd : null, ['requirements','overview'].includes(section) ? data.north?.content : null, data.failed && ['files','tasks'].includes(section)]);
    const header=container.closest('.chat-area')?.querySelector('.project-tabs');
-    if(header){const tasks=header.querySelector(`a[href="${path(project.id,'tasks')}"]`), files=header.querySelector(`a[href="${path(project.id,'files')}"]`);const f=filesData(data);if(tasks && !tasks.querySelector('.project-count') && !data.failed)tasks.insertAdjacentHTML('beforeend',` <span class="project-count">${taskRefs(data).length}</span>`);if(files && !files.querySelector('.project-count') && !data.failed && f.docs && data.requests.every(r=>r.workspace?.available===true && Array.isArray(r.workspace.entries)))files.insertAdjacentHTML('beforeend',` <span class="project-count">${f.reviewed.length+f.drafts.length+f.docs.length}</span>`);}
+    if(header){const tab=key=>header.querySelector(`a[href$="${path(project.id,key).slice(1)}"]`), tasks=tab('tasks'), files=tab('files');const f=filesData(data);if(tasks && !tasks.querySelector('.project-count') && !data.failed)tasks.insertAdjacentHTML('beforeend',` <span class="project-count">${taskRefs(data).length}</span>`);if(files && !files.querySelector('.project-count') && !data.failed && f.docs && data.requests.every(r=>r.workspace?.available===true && Array.isArray(r.workspace.entries)))files.insertAdjacentHTML('beforeend',` <span class="project-count">${f.reviewed.length+f.drafts.length+f.docs.length}</span>`);}
    revealTab(header);
    // Retained controls (the request selector) draw from the newest accepted read, even when
    // this read changes nothing visible and the DOM is kept.
    contentModels.set(container,{data,project,section,canSend,roomReceipt});
-    window.MosaicOnboarding?.offer(container,{project,section,north:data.north,docs:data.docs,threads:data.threads,canSend}); // F2: its panel sits before the container, outside draw().
+    if(!pane) window.MosaicOnboarding?.offer(container,{project,section,north:data.north,docs:data.docs,threads:data.threads,canSend}); // F2: its panel sits before the container, outside draw().
    if (contentPaints.get(container) === signature) return;
    contentPaints.set(container, signature);
    // Capture at commit time: the user may have interacted while the read was pending.
@@ -273,7 +285,7 @@
    const liveRestore=contentPaints.has(container) && container.children.length ? captureView(container) : null;
    const draw=selected=>{
      const {data,project,section,canSend,roomReceipt}=contentModels.get(container);
-      container.innerHTML=section==='requirements'?requirementView(data,project,selected):section==='files'?filesView(data,project):section==='tasks'?tasksView(data):overview(data,project,canSend,roomReceipt);
+      container.innerHTML=section==='requirements'?requirementView(data,project,selected,expandedPrds):section==='files'?filesView(data,project):section==='tasks'?tasksView(data):overview(data,project,canSend,roomReceipt);
      if(data.failed && ['files','tasks'].includes(section)) container.insertAdjacentHTML('afterbegin','<p role="status">Some request data could not be read; this list may be incomplete.</p>');
      const selectedRequest=data.requests.find(r=>r.id===(selected||data.requests.find(x=>x.draft)?.id));
      const md=container.querySelector('[data-prd]'); if(md && selectedRequest?.draft) { md.replaceChildren(window.MosaicMarkdown?.render(selectedRequest.draft.prd) || document.createTextNode(selectedRequest.draft.prd)); const toggle=container.querySelector('.project-prd-toggle'); toggle.hidden=!md.classList.contains('expanded') && md.scrollHeight<=md.clientHeight; toggle.addEventListener('click',()=>{const key=project.id+':'+selectedRequest.id; if(expandedPrds.has(key)) expandedPrds.delete(key); else expandedPrds.add(key); const open=expandedPrds.has(key); md.classList.toggle('expanded',open); toggle.setAttribute('aria-expanded',String(open));toggle.textContent=open?'Show less':'Show full PRD';}); }
@@ -285,7 +297,7 @@
    if (restore) {
      restoreView(container,restore);
    }
-    const sectionTarget=new URLSearchParams(location.hash.split('?')[1] || '').get('section');
+    const sectionTarget=pane ? null : new URLSearchParams(location.hash.split('?')[1] || '').get('section');
    if(section==='requirements' && ['prd','north-star'].includes(sectionTarget)) container.querySelector('#project-'+sectionTarget)?.scrollIntoView({block:'start'});
  }
  // Cut at a word boundary, unless that would leave only a markdown marker (a long heading).
@@ -334,7 +346,7 @@
  }
  const palette=()=>treeRows.filter(p=>!p.archived && UUID.test(p.id)).flatMap(p=>sections.map(([key,label])=>({href:path(p.id,key),label:key==='overview'?p.name:`${p.name}: ${label}`,group:'project'})));
  function breadcrumb(box, view) {
-    const h=view.querySelector('.project-header'); if(!h)return false;
+    const h=view.querySelector('.project-header'); if(!h||h.closest('[data-pane]'))return false;
    const id=h.dataset.projectId, name=h.dataset.projectName, section=h.dataset.projectSection, conversation=h.dataset.projectConversation==='true';
    const title=sections.find(([key])=>key===section)?.[1] || (section==='settings'?'Settings':'Overview');
    const leaf=conversation?view.querySelector('h1')?.textContent:title;
@@ -0,0 +1,33 @@
+/* Phase P2 (#1873): System types on the organization dashboard (.ws-types, the chips and the
+   Settings row's Open) and on a project's information page (.project-types). */
+html[data-organizations] .ws-chip{display:inline-flex;align-items:center;font-size:12px;font-weight:500;padding:1px 7px;border:1px solid var(--line);border-radius:4px;color:var(--text);white-space:nowrap}
+html[data-organizations] .ws-cfg button.go{border:0;background:none;padding:0;cursor:pointer;font:inherit;font-size:12.5px;font-weight:600;color:var(--action)}
+html[data-organizations] .ws-cfg button.go:hover{text-decoration:underline}
+html[data-organizations] .ws-types-list{display:grid;list-style:none;margin:0;padding:0;border:1px solid var(--line);border-radius:8px;overflow:hidden;background:var(--surface)}
+html[data-organizations] .ws-types-list li{display:grid;grid-template-columns:minmax(0,1fr) auto auto;align-items:center;gap:4px 12px;padding:8px 12px;border-bottom:1px solid color-mix(in srgb,var(--line) 60%,transparent)}
+html[data-organizations] .ws-types-list li:last-child{border-bottom:0}
+html[data-organizations] .ws-types-list .t{display:flex;flex-direction:column;min-width:0}
+html[data-organizations] .ws-types-list .t b{font-size:13px;font-weight:600;color:var(--strong)}
+html[data-organizations] .ws-types-list .t .d{font-size:12px;color:var(--muted);overflow-wrap:anywhere}
+html[data-organizations] .ws-types-list .ws-dot{font-size:12.5px}
+html[data-organizations] .ws-types-list .ws-btn[aria-disabled="true"]{color:var(--muted);cursor:progress}
+html[data-organizations] .ws-types>.note{margin:8px 0 0}
+html[data-organizations] .ws-types-status:empty{display:none}
+html[data-organizations] .ws-types-status code{overflow-wrap:anywhere}
+html[data-organizations] .ws-types h2:focus{outline:none}
+@media (max-width:759px){
+  html[data-organizations] .ws-types-list li{grid-template-columns:minmax(0,1fr) auto}
+  html[data-organizations] .ws-types-list .t{grid-column:1/-1}
+}
+
+.project-types{border:1px solid var(--border, var(--line, #aaa));border-radius:4px;padding:1rem;margin-top:1rem;overflow-wrap:anywhere}
+.project-types fieldset{border:0;margin:0;padding:0;display:grid;gap:.5rem}
+.project-types legend{font-weight:600;margin-bottom:.25rem}
+.project-types-option{display:flex;align-items:flex-start;gap:.5rem;min-height:44px}
+.project-types-option input{margin-top:.2rem;width:20px;height:20px;flex:none}
+.project-types-option span{display:flex;flex-direction:column;min-width:0}
+.project-types-option small{color:var(--muted, inherit)}
+.project-types button{min-height:44px;margin-top:.75rem}
+.project-types-tag{font-size:.8em;font-weight:600;padding:0 .4em;border:1px solid currentColor;border-radius:4px;color:var(--warning, inherit)}
+.project-types [role="status"]:empty{display:none}
+.project-types [role="status"]:focus{outline:none}
@@ -0,0 +1,195 @@
+// Phase P2 (#1873): System types, the owner's control on the organization dashboard and on a project's
+// information page. The modules, their labels and descriptions come from the system-type plug-ins
+// through /api/system-types; nothing here lists a module. Writes go to the same route, which uses the
+// organization writer (revision, owner fence, receipt) or project.system-types.set; the server and the
+// bus recheck every write, so a control shown here grants nothing.
+(() => {
+  'use strict';
+  const esc = value => String(value ?? '').replace(/[&<>"']/g, c => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' }[c]));
+  const enc = encodeURIComponent;
+  const ID = /^[A-Za-z0-9][A-Za-z0-9._-]{0,159}$/;
+  const orgPath = (org, rest) => (org ? `/api/orgs/${enc(org)}/${rest}` : `/api/${rest}`);
+  const LINES = {
+    'sign-in-required': 'Sign in again to see or change system types.',
+    'owner-only': "System types are the organization owner's.",
+    'read-only': 'This Console only reads. Changing system types needs signed-in send mode.',
+    'human-required': "Only the organization's owner can change system types.",
+    'organization-system-types-human-only': "Only the organization's owner can change system types.",
+    'revision-conflict': 'The organization file changed after this page read it. The list was read again; try again.',
+    'organization-busy': 'The organization file is being written. Try again in a moment.',
+    'system-type-not-enabled': 'A chosen type is not enabled in the organization any more. The list was read again.',
+    'system-type-unknown': 'A chosen type is not installed in this tree.',
+    'project-not-found': 'This project was not found.',
+    'not-configured': 'System types are not configured on this Console.',
+    'system-type-invalid': 'An installed system type module is invalid, so none can be read.',
+    'no-bus-host': 'The bus is not running.',
+    'invalid-request': 'The request was refused as invalid.',
+  };
+  const line = code => LINES[code] || 'The bus did not confirm the outcome. The list was read again; check it before you retry.';
+
+  // One request; a refusal keeps its code so the page can say why.
+  async function call(path, body) {
+    const init = body === undefined ? { cache: 'no-store', redirect: 'manual' }
+      : { method: 'POST', cache: 'no-store', redirect: 'manual', headers: { 'content-type': 'application/json' }, body: JSON.stringify(body) };
+    let response;
+    try { response = await fetch(path, init); } catch { return { ok: false, code: 'outcome-unknown' }; }
+    if (response.type === 'opaqueredirect') return { ok: false, code: 'sign-in-required' };
+    const value = await response.json().catch(() => null);
+    if (!response.ok) return { ok: false, code: typeof value?.error === 'string' ? value.error : 'outcome-unknown' };
+    return value && typeof value === 'object' ? { ok: true, value } : { ok: false, code: 'outcome-unknown' };
+  }
+  const read = (org, project = null) => call(orgPath(org, project === null ? 'system-types' : `system-types/projects/${enc(project)}`));
+  const labelOf = (value, id) => value.installed.find(m => m.id === id)?.label || id;
+  const valid = value => value && Array.isArray(value.installed) && Array.isArray(value.enabled);
+
+  // ---------- organization dashboard ----------
+  // Per organization: the last read, the type a write is pending on, and the last outcome line.
+  const orgs = new Map();
+  const slot = org => { if (!orgs.has(org)) orgs.set(org, { value: null, code: null, pending: null, outcome: null }); return orgs.get(org); };
+  function remember(org, result) {
+    const s = slot(org);
+    if (result.ok && valid(result.value)) { s.value = result.value; s.code = null; } else { s.value = null; s.code = result.ok ? 'outcome-unknown' : result.code; }
+    return s;
+  }
+  // The chip row under the header: the enabled modules' labels.
+  function chips(org) {
+    const s = slot(org), v = s.value;
+    const body = !v ? `<span class="note">${esc(s.code === 'owner-only' ? line('owner-only') : 'System types unavailable')}</span>`
+      : !v.installed.length ? '<span class="note">No system type modules are installed.</span>'
+      : v.enabled.length ? `${v.enabled.map(id => `<span class="ws-chip">${esc(labelOf(v, id))}</span>`).join('')}<span class="note">Each project picks from these; none is required.</span>`
+      : '<span class="note">None enabled. Enable them under System types below; each project picks from the enabled ones.</span>';
+    return `<div class="ws-typechips ws-chips" data-system-type-chips><span class="ws-label">System types</span>${body}</div>`;
+  }
+  // The Settings row's value.
+  function summary(org) {
+    const v = slot(org).value;
+    return v ? `${v.enabled.filter(id => v.installed.some(m => m.id === id)).length} of ${v.installed.length} installed enabled` : 'Could not be read';
+  }
+  // A side-by-side pane (U5) passes { pane: true, idPrefix }: it shows the types without the switch,
+  // which stays in the organization's full view, and its heading id carries the pane's prefix.
+  function section(org, { pane = false, idPrefix = '' } = {}) {
+    const s = slot(org), v = s.value;
+    const head = `<div class="ws-sec-h"><h2 id="${esc(idPrefix)}ws-types-h" tabindex="-1" data-system-types-heading>System types</h2><span class="note">installed modules; each project picks from the enabled ones</span></div>`;
+    const status = `<p class="note ws-types-status" role="status" data-system-types-status>${s.outcome ? s.outcome : ''}</p>`;
+    if (!v) return `<div class="ws-types" data-system-types>${head}<p class="ws-panel tight note">${esc(s.code === 'owner-only' ? line('owner-only') : `System types unavailable. ${line(s.code)}`)}</p>${status}</div>`;
+    if (!v.installed.length) return `<div class="ws-types" data-system-types>${head}<p class="ws-panel tight note">No system type modules are installed.</p>${status}</div>`;
+    const rows = v.installed.map(m => {
+      const on = v.enabled.includes(m.id), busy = s.pending !== null;
+      const state = `<span class="ws-dot ${on ? 's-working' : 's-idle'}"><b aria-hidden="true">${on ? '●' : '–'}</b>${on ? 'enabled' : 'off'}</span>`;
+      const control = v.writable && !pane
+        ? `<button type="button" class="ws-btn" data-system-type-toggle="${esc(m.id)}" data-on="${on}" data-focus-key="${esc(`st:${m.id}`)}" aria-label="${esc(`${on ? 'Disable' : 'Enable'} ${m.label}`)}"${busy ? ' aria-disabled="true"' : ''}>${s.pending === m.id ? 'Saving…' : on ? 'Disable' : 'Enable'}</button>`
+        : '';
+      return `<li data-system-type="${esc(m.id)}"><span class="t"><b>${esc(m.label)}</b><span class="d">${esc(m.description)}</span></span>${state}${control}</li>`;
+    }).join('');
+    const why = pane ? "<p class=\"note\">Change system types from this organization's full view.</p>"
+      : v.writable ? '<p class="note">Disabling a type keeps it in the projects that pick it; they show it as inactive until it is enabled again.</p>'
+      : `<p class="note">${esc(line('read-only'))}</p>`;
+    return `<div class="ws-types" data-system-types>${head}<ul class="ws-types-list">${rows}</ul>${why}${status}</div>`;
+  }
+  // The dashboard asks for this before it paints; the result stays for chips(), summary() and section().
+  const load = async org => remember(org, await read(org));
+  // After a write, the three parts are repainted in place; the 10 s dashboard repaint reads again anyway.
+  function repaint(org) {
+    if (window.MosaicOrg?.id !== org) return;
+    const view = [...document.querySelectorAll('[data-org-dashboard]')].find(v => !v.closest('[data-pane]')); if (!view) return;
+    const a = document.activeElement, key = view.contains(a) ? a.dataset?.focusKey || null : null;
+    const swap = (selector, html) => { const el = view.querySelector(selector); if (el) el.outerHTML = html; };
+    swap('[data-system-type-chips]', chips(org));
+    swap('[data-system-types]', section(org));
+    const value = view.querySelector('[data-org-setting="System types"] .v'); if (value) { value.textContent = summary(org); value.title = summary(org); }
+    if (key) view.querySelector(`[data-focus-key="${CSS.escape(key)}"]`)?.focus({ preventScroll: true });
+  }
+  async function toggle(button) {
+    const org = window.MosaicOrg?.id, s = org ? slot(org) : null, type = button.dataset.systemTypeToggle;
+    if (!s?.value?.writable || s.pending !== null || typeof s.value.revision !== 'string') return;
+    const on = s.value.enabled.includes(type);
+    const enabled = on ? s.value.enabled.filter(id => id !== type) : [...s.value.enabled, type];
+    s.pending = type; s.outcome = null; repaint(org);
+    const result = await call(orgPath(org, 'system-types'), { revision: s.value.revision, enabled });
+    s.pending = null;
+    const label = labelOf(s.value, type);
+    if (result.ok && typeof result.value.transaction === 'string') {
+      s.outcome = `${esc(label)} ${on ? 'disabled' : 'enabled'}. Receipt <code>${esc(result.value.transaction)}</code>.`;
+    } else s.outcome = esc(result.ok ? line('outcome-unknown') : line(result.code));
+    await load(org);
+    repaint(org);
+  }
+  document.addEventListener('click', e => {
+    const button = e.target.closest?.('[data-system-type-toggle]');
+    // A pending write marks the buttons aria-disabled, not disabled, so focus stays on the one pressed.
+    if (button) { e.preventDefault(); if (button.getAttribute('aria-disabled') !== 'true' && !button.closest('[data-pane]')) toggle(button); return; }
+    const open = e.target.closest?.('[data-system-types-open]');
+    if (open) { e.preventDefault(); const h = (open.closest('[data-org-dashboard]') || document).querySelector('[data-system-types-heading]'); h?.scrollIntoView({ block: 'start' }); h?.focus({ preventScroll: true }); }
+  });
+
+  // ---------- project information page ----------
+  let active = null;
+  document.addEventListener('mosaic-signed-out', () => { active?.dispose(); active = null; });
+  // The chat view mounts again on every repaint and keeps the section; leaving the page marks it stale,
+  // so coming back (say, after the dashboard changed the enabled set) reads again.
+  window.addEventListener('hashchange', () => { if (active) active.stale = true; });
+  function mount({ container, projectId, archived = false }) {
+    if (!(container instanceof Element)) return;
+    const org = window.MosaicOrg?.id ?? null;
+    if (active && active.org === org && active.projectId === projectId) {
+      container.replaceChildren(active.section);
+      if (active.archived !== archived) { active.archived = archived; active.paint(); }
+      if (active.stale) { active.stale = false; active.refresh(); }
+      return;
+    }
+    active?.dispose();
+    const section = document.createElement('section');
+    section.className = 'project-types';
+    section.setAttribute('data-project-system-types', '');
+    container.replaceChildren(section);
+    let value = null, code = null, outcome = '', saving = false, disposed = false, generation = 0;
+    const state = { org, projectId, section, archived, stale: false, paint, refresh: () => refresh(), dispose: () => { disposed = true; generation++; section.replaceChildren(); } };
+    active = state;
+    function paint() {
+      if (disposed) return;
+      const head = '<h2 tabindex="-1">System types</h2>';
+      const status = `<p role="status" tabindex="-1" data-project-system-types-status>${outcome}</p>`;
+      if (!ID.test(projectId ?? '')) { section.innerHTML = `${head}<p>System types unavailable.</p>`; return; }
+      if (!value) { section.innerHTML = `${head}<p>${esc(code ? `System types unavailable. ${line(code)}` : 'Reading system types…')}</p>${status}`; return; }
+      const sel = value.project, enabled = value.installed.filter(m => value.enabled.includes(m.id));
+      const inactive = sel.inactive.length
+        ? `<div data-project-system-types-inactive><p>Inactive, because the organization has disabled them:</p><ul>${sel.inactive.map(id => `<li data-inactive-type="${esc(id)}">${esc(labelOf(value, id))} <span class="project-types-tag">inactive</span></li>`).join('')}</ul>${value.writable && !state.archived ? '<p class="muted">Saving keeps only enabled types, so it removes these from the project.</p>' : ''}</div>`
+        : '';
+      const intro = '<p>This project picks from the system types its organization has enabled. None is required.</p>';
+      const canWrite = value.writable && !state.archived;
+      if (!enabled.length) {
+        // With nothing enabled the only change left is clearing what the project still selects.
+        const clear = canWrite && sel.inactive.length
+          ? `<form data-project-system-types-form><button type="submit" class="btn"${saving ? ' disabled' : ''}>${saving ? 'Saving…' : 'Clear the inactive types'}</button></form>` : '';
+        section.innerHTML = `${head}${intro}<p>The organization has no system types enabled. The owner enables them on the organization dashboard.</p>${inactive}${clear}${status}`;
+        return;
+      }
+      const boxes = enabled.map(m => `<label class="project-types-option"><input type="checkbox" name="system-type" value="${esc(m.id)}"${sel.active.includes(m.id) ? ' checked' : ''}${canWrite && !saving ? '' : ' disabled'}><span><strong>${esc(m.label)}</strong><small>${esc(m.description)}</small></span></label>`).join('');
+      const why = state.archived ? '<p class="muted">This project is archived; its selection is shown read only.</p>' : value.writable ? '' : `<p class="muted">${esc(line('read-only'))}</p>`;
+      section.innerHTML = `${head}${intro}<form data-project-system-types-form><fieldset><legend>Selected system types</legend>${boxes}</fieldset>${inactive}${canWrite ? `<button type="submit" class="btn"${saving ? ' disabled' : ''}>${saving ? 'Saving…' : 'Save system types'}</button>` : ''}</form>${why}${status}`;
+    }
+    async function refresh() {
+      const turn = ++generation;
+      const result = await read(org, projectId);
+      if (disposed || turn !== generation) return;
+      if (result.ok && valid(result.value) && result.value.project) { value = result.value; code = null; } else { value = null; code = result.ok ? 'outcome-unknown' : result.code; }
+      paint();
+    }
+    section.addEventListener('submit', async e => {
+      e.preventDefault();
+      if (saving || !value?.writable || state.archived) return;
+      const chosen = [...section.querySelectorAll('input[name="system-type"]:checked')].map(i => i.value);
+      saving = true; outcome = ''; paint();
+      const result = await call(orgPath(org, `system-types/projects/${enc(projectId)}`), { systemTypes: chosen });
+      if (disposed) return;
+      saving = false;
+      outcome = result.ok ? esc(result.value.selected.length ? `Saved. Selected: ${result.value.selected.map(id => labelOf(value, id)).join(', ')}.` : 'Saved. No system types selected.') : esc(line(result.code));
+      await refresh();
+      section.querySelector('[data-project-system-types-status]')?.focus({ preventScroll: true });
+    });
+    paint();
+    refresh();
+  }
+
+  window.MosaicSystemTypes = Object.freeze({ load, chips, summary, section, mount });
+})();
@@ -1,7 +1,8 @@
 // The unified workspace screens in organization mode: the sidebar's Organizations and Projects
 // groups (sample 01), the organization dashboard (sample 03) and the Agents levels (sample 08).
 // Every read goes through MosaicWorkspaceData (workspace-data.js). Nothing here writes; the bus
-// restart button is console-restart.js's own control, with its gating and trail unchanged.
+// restart button is console-restart.js's own control, with its gating and trail unchanged, and the
+// System types chips, row and section are system-types.js's (Phase P2), with its own reads and writes.
 (() => {
  'use strict';
  if (!document.documentElement.hasAttribute('data-organizations')) return;
@@ -154,7 +155,7 @@
  const secH = (title, note = '', link = '') => `<div class="ws-sec-h"><h2>${title}</h2>${note ? `<span class="note">${note}</span>` : ''}${link}</div>`;

  function settingsList(org, ctx) {
-    const { business, settings, instances, orgCount } = ctx;
+    const { business, settings, instances, orgCount, types } = ctx;
    const b = business?.business, s = settings;
    const unread = 'Could not be read';
    const names = instances ? Object.keys(instances) : null;
@@ -166,7 +167,7 @@
    const rows = [
      ['business', 'Identity', b ? `${label(org)} · ${org.id} · kind not recorded` : unread, 'org file', 'business'],
      ['flag', 'Appearance', `${titleCase(theme)} theme · ${initials(org)} avatar`, b?.appearance?.theme || org.theme ? 'org file' : 'system', 'appearance'],
-      ['cube', 'System types', 'Not built yet', 'not built', null],
+      ['cube', 'System types', types ? types.summary(org.id) : 'Could not be read', 'org file', types ? '@system-types' : null],
      ['folder', 'Projects', b ? (Array.isArray(b.projects) && b.projects.length ? plural(b.projects.length, 'project') : 'No projects') : unread, 'org file', '#/projects'],
      ['people', 'Agents and roles', names ? (names.length ? `${plural(names.length, 'agent')} · ${Object.values(instances).filter(running).length} running` : 'No agents') : unread, 'org file', 'agents'],
      ['term', 'Models and routing', models ? (models.length ? models.join(' · ') : 'No models set') : unread, 'org file', 'routing'],
@@ -185,20 +186,25 @@
      ['close', 'Archive or delete', "Archive or delete this organization's file", 'danger', 'organizations'],
    ];
    return `<ul class="ws-cfg one" data-org-settings>${rows.map(([ic, name, value, tag, page]) => {
-      const href = page === null ? null : page.startsWith('#') ? page : `#/settings/${page}`;
-      const go = href ? `<a class="go" href="${esc(href)}" data-focus-key="${esc(`set:${name}`)}" aria-label="Open ${esc(name)}">Open</a>` : '<span class="go" aria-hidden="true"></span>';
+      const href = page === null || page.startsWith('@') ? null : page.startsWith('#') ? page : `#/settings/${page}`;
+      // '@system-types' is the System types section further down this page, not a route.
+      const go = page === '@system-types' ? `<button type="button" class="go" data-system-types-open data-focus-key="${esc(`set:${name}`)}" aria-label="Open ${esc(name)}">Open</button>`
+        : href ? `<a class="go" href="${esc(href)}" data-focus-key="${esc(`set:${name}`)}" aria-label="Open ${esc(name)}">Open</a>` : '<span class="go" aria-hidden="true"></span>';
      return `<li${tag === 'danger' ? ' class="danger"' : ''} data-org-setting="${esc(name)}">${icon(ic)}<span class="k">${esc(name)}</span><span class="v" title="${esc(value)}">${esc(value)}</span><span class="src-tag">${esc(tag)}</span>${go}</li>`;
    }).join('')}</ul>`;
  }

-  async function dashboard() {
-    const id = window.MosaicOrg.id;
+  // A side-by-side pane passes its own organization and { pane: true, idPrefix }: the pane has no bus
+  // restart (that stays in the organization's full view) and its ids carry the pane's prefix.
+  async function dashboard(id = window.MosaicOrg.id, opts = {}) {
+    const pane = opts.pane === true, why = `${opts.idPrefix || ''}ws-reload-why`;
    // Only an organization the membership list names is read; anything else reads nothing more.
    const [listRead] = await Promise.all([data.organizations().catch(() => null), ensureThemes()]);
    const list = Array.isArray(listRead) ? listRead : null;
    const org = list?.find(o => o.id === id && !o.invalid);
    if (!org) return `<article class="ws ws-dash" data-org-dashboard data-org-unavailable><div class="ws-vh"><h1 tabindex="-1">Organization unavailable</h1><p class="sub">${list ? 'This organization is not on your list.' : 'The organization list could not be read.'}</p></div></article>`;
-    const reads = await Promise.allSettled([data.business(id), data.settings(id), data.instances(id), data.threads(id), data.projects(id), data.queue(id), data.agents(id), data.claims(id)]);
+    const types = window.MosaicSystemTypes || null;
+    const reads = await Promise.allSettled([data.business(id), data.settings(id), data.instances(id), data.threads(id), data.projects(id), data.queue(id), data.agents(id), data.claims(id), types ? types.load(id) : null]);
    const value = i => (reads[i].status === 'fulfilled' ? reads[i].value : null);
    const business = value(0), settings = value(1), instances = instancesOf(value(2));
    const threads = rowsOf(value(3)), projectRows = rowsOf(value(4)), queue = rowsOf(value(5));
@@ -210,14 +216,15 @@

    // Header: the bus restart is console-restart.js's button where the Console allows it, otherwise
    // the same control, present and disabled, with the reason.
-    const restart = window.MosaicConsole?.busButton?.('Restart bus') || '';
-    const bus = restart ? `<span class="ws-busctl" data-dashboard-bus>${icon('restart', 'ws-busicon')}${restart}</span>` : `<span data-dashboard-bus><button type="button" class="ws-btn" data-bus-restart-off data-focus-key="bus-restart-off" disabled title="Restarting the bus is the owner's trailed action, on a Console started with send and the action trail">${icon('restart')}Restart bus</button></span>`;
-    const reload = `<button type="button" class="ws-btn" data-org-reload data-focus-key="org-reload" disabled aria-describedby="ws-reload-why" title="Reload arrives with the cross-org update">${icon('doc')}Reload organization file</button>`;
+    const restart = pane ? '' : window.MosaicConsole?.busButton?.('Restart bus') || '';
+    const offTitle = pane ? "Restart the bus from this organization's full view" : "Restarting the bus is the owner's trailed action, on a Console started with send and the action trail";
+    const bus = restart ? `<span class="ws-busctl" data-dashboard-bus>${icon('restart', 'ws-busicon')}${restart}</span>` : `<span data-dashboard-bus><button type="button" class="ws-btn" data-bus-restart-off data-focus-key="bus-restart-off" disabled title="${esc(offTitle)}">${icon('restart')}Restart bus</button></span>`;
+    const reload = `<button type="button" class="ws-btn" data-org-reload data-focus-key="org-reload" disabled aria-describedby="${esc(why)}" title="Reload arrives with the cross-org update">${icon('doc')}Reload organization file</button>`;
    const [bcls, bglyph] = state(org);
-    const meta = `<p class="ws-meta"><span>Kind not recorded</span><span>id <code>${esc(id)}</code></span><span>Tracker: ${tracker ? esc(titleCase(tracker)) : 'not set'}</span><span>${dot(bcls, bglyph, org.busHealthy ? `bus running, read ${clock()}` : `bus unavailable, read ${clock()}`, true)}</span><span id="ws-reload-why">Restart is a trailed human action; reload arrives with the cross-org update.</span></p>`;
+    const meta = `<p class="ws-meta"><span>Kind not recorded</span><span>id <code>${esc(id)}</code></span><span>Tracker: ${tracker ? esc(titleCase(tracker)) : 'not set'}</span><span>${dot(bcls, bglyph, org.busHealthy ? `bus running, read ${clock()}` : `bus unavailable, read ${clock()}`, true)}</span><span id="${esc(why)}">Restart is a trailed human action; reload arrives with the cross-org update.</span></p>`;

    const projectName = pid => projectRows?.find(p => p.id === pid)?.name || pid;
-    const typechips = '<div class="ws-typechips ws-chips"><span class="ws-label">System types</span><span class="note">No system types yet. They arrive with the system types update.</span></div>';
+    const typechips = types ? types.chips(id) : '<div class="ws-typechips ws-chips"><span class="ws-label">System types</span><span class="note">System types unavailable</span></div>';
    const docChips = !docRead ? '<span class="note">Docs unavailable</span>' : docRead.failed ? '<span class="note">Docs unavailable</span>' : docRead.rows.length ? docRead.rows.slice(0, 6).map(d => `<a class="ws-doc" href="#/docs/${enc(d.project)}/${enc(d.path)}" data-focus-key="${esc(`doc:${d.project}:${d.path}`)}" title="${esc(`${d.project}/${d.path}`)}">${icon('doc')}${esc(docName(d.path))}<small>${esc(projectName(d.project))}</small></a>`).join('') : '<span class="note">No docs yet</span>';
    const docrow = `<div class="ws-docrow ws-chips"><span class="ws-label">Docs</span>${docChips}<a class="ws-more" href="#/docs" data-focus-key="docs-all">All docs</a></div>`;

@@ -255,7 +262,8 @@
        </section>
        <section aria-label="Settings">
          ${secH('Settings', 'every setting, with where its value comes from')}
-          ${settingsList(org, { business, settings, instances, orgCount: list ? list.length : null })}
+          ${settingsList(org, { business, settings, instances, orgCount: list ? list.length : null, types })}
+          ${types ? types.section(id, { pane, idPrefix: opts.idPrefix || '' }) : ''}
        </section>
      </div>
    </article>`;
@@ -269,7 +277,9 @@
  const LEVEL_CLS = { root: 'root', org: 'org', project: 'proj' };
  const projectName = (rows, id) => { const p = Array.isArray(rows) ? rows.find(r => r?.id === id) : null; return p?.name || id; };
  let agentsPick = null; // the project chosen in "Available in a project", kept across repaints
-  let agentsAvailable = null; // repaints that section alone when the choice changes
+  // Repaints that section alone when the choice changes, one renderer per organization: a side-by-side
+  // pane can show another organization's agents next to the page's own.
+  let agentsAvailable = {};

  function levelsTable(ctx, projectId) {
    const { selOrg, lv, mine, levels, modelOf, names, others } = ctx;
@@ -322,9 +332,8 @@
    return `<div class="ws-tbl"><table><thead><tr><th scope="col">Agent</th><th scope="col">Level</th><th scope="col" class="hide-m">Defined in</th><th scope="col" class="hide-m">Memory</th><th scope="col">Status</th><th scope="col" class="hide-m">Model</th></tr></thead><tbody>${body}</tbody></table></div>${note}`;
  }

-  async function agentGrid(note = '') {
+  async function agentGrid(note = '', selected = window.MosaicOrg?.id) {
    const [list, levels] = await Promise.all([data.organizations().catch(() => null), data.agentLevels().catch(() => null), ensureThemes()]);
-    const selected = window.MosaicOrg?.id;
    const head = `<div class="ws-vh"><h1 tabindex="-1">Agents</h1><div class="ws-right"><a class="ws-btn" href="#/settings/agents" data-focus-key="agents-edit">${icon('settings')}Edit agents</a></div><p class="sub">Agents are defined at three levels: root, organization and project. Root and project agents are read from their files and are not launched yet.${note ? ` ${note}` : ''}</p></div>`;
    if (!Array.isArray(list)) return `<section class="ws ws-agents" data-org-agents>${head}<p class="ws-panel tight note">Organizations unavailable.</p></section>`;
    const valid = list.filter(org => !org.invalid);
@@ -372,8 +381,8 @@
    const projectIds = lv?.state === 'ok' ? Object.keys(lv.projects) : [];
    const pick = projectIds.includes(agentsPick?.[selected]) ? agentsPick[selected] : projectIds[0] ?? null;
    const ctx = { selOrg, lv, mine, levels, modelOf, names: id => projectName(mine?.rows, id), others: valid.filter(o => o.id !== selected) };
-    agentsAvailable = projectId => levelsTable(ctx, projectId);
-    const chooser = projectIds.length ? `<label class="ws-psel">${av(selOrg, 'xs')}<span class="ws-sr">Project</span><select data-agents-project data-focus-key="agents-project">${projectIds.map(id => `<option value="${esc(id)}"${id === pick ? ' selected' : ''}>${esc(ctx.names(id))}</option>`).join('')}</select></label>` : '';
+    agentsAvailable = { ...agentsAvailable, [selected]: projectId => levelsTable(ctx, projectId) };
+    const chooser = projectIds.length ? `<label class="ws-psel">${av(selOrg, 'xs')}<span class="ws-sr">Project</span><select data-agents-project="${esc(selected)}" data-focus-key="agents-project">${projectIds.map(id => `<option value="${esc(id)}"${id === pick ? ' selected' : ''}>${esc(ctx.names(id))}</option>`).join('')}</select></label>` : '';
    const title = projectIds.length ? 'Available in a project' : `Agents in ${esc(label(selOrg))}`;
    const table = !mine ? '<p class="ws-panel tight note">The selected organization is not on the list.</p>' : levelsTable(ctx, pick);
    const rules = `<div class="ws-panel tight ws-rules"><p><span class="ws-lvl root">root</span>You define root agents in agents.json in your configuration directory. The chief cannot change them.</p><p><span class="ws-lvl org">org</span>Agents come from the organization file. Add, change or remove them under Settings, Agents.</p><p><span class="ws-lvl proj">project</span>A project in the organization file can add an agent, narrow an inherited agent's limits or exclude one. It never widens them.</p><p><span class="ws-lvl proj">override</span>The most specific level wins. A row says which definition it replaces.</p><p class="muted">An agent's harness, model and thinking are set under Settings, Routing.</p></div>`;
@@ -383,10 +392,11 @@
  }
  document.addEventListener('change', e => {
    const select = e.target.closest?.('[data-agents-project]');
-    const box = select && document.querySelector('[data-agents-available]');
-    if (!box || !agentsAvailable || !window.MosaicOrg) return;
-    agentsPick = { ...agentsPick, [window.MosaicOrg.id]: select.value };
-    box.innerHTML = agentsAvailable(select.value);
+    const org = select?.dataset.agentsProject, draw = org && Object.hasOwn(agentsAvailable, org) ? agentsAvailable[org] : null;
+    const box = draw && select.closest('[data-org-agents]')?.querySelector('[data-agents-available]');
+    if (!box) return;
+    agentsPick = { ...agentsPick, [org]: select.value };
+    box.innerHTML = draw(select.value);
  });

  // ---------- across organizations (U3: samples 02, 04 and 05) ----------
@@ -737,6 +747,6 @@

  // U4b: the org mark (colour and initials) for the task board (tasks-board.js).
  const orgMark = Object.freeze({ ready: ensureThemes, av, colours, initials });
-  window.MosaicWorkspace = Object.freeze({ dashboard, agentGrid, icon, orgMark, refresh: () => refresh(), home, projectsPage, inboxPage, setGrouping, get pollMs() { return pollMs; } });
+  window.MosaicWorkspace = Object.freeze({ dashboard, agentGrid, icon, orgMark, refresh: () => refresh(), av, colours, label, state, dot, themes: ensureThemes, home, projectsPage, inboxPage, setGrouping, get pollMs() { return pollMs; } });
  refresh();
 })();
@@ -18,6 +18,7 @@ import { themesHTTP } from './themes-http.mjs';
 import { DECISION_ROUTE, decisionHTTP, decisionRefuse, createConfirmations } from './decision-http.mjs';
 import { REQUEST_ROUTE, requestHTTP, requestRefuse } from './request-http.mjs';
 import { PROJECT_REMOTE_ROUTE, projectRemoteHTTP } from './project-remote-http.mjs';
+import { SYSTEM_TYPES_ROUTE, systemTypesHTTP } from './system-types-http.mjs';
 import { orgAdminHTTP, defaultOrgAdmin } from './org-admin.mjs';
 import { consoleRestartHTTP } from './console-restart-http.mjs';
 import { workspaceHTTP } from './workspace-read.mjs';
@@ -60,12 +61,12 @@ const files = new Map([
  ['/', ['index.html', 'text/html; charset=utf-8']],
  ['/proxy.js', ['proxy.js', 'text/javascript; charset=utf-8']],
  ['/project-remote.js', ['project-remote.js', 'text/javascript; charset=utf-8']],
-  ...['app.js', 'brand.js', 'bus.js', 'markdown-preview.js', 'chat.js', 'project-archive.js', 'processing.js', 'agents.js', 'federation.js', 'requests.js', 'org-create.js', 'console-restart.js', 'onboarding.js', 'workspace-data.js', 'workspace.js', 'tasks-board.js'].map(f => ['/' + f, [f, 'text/javascript; charset=utf-8']]),
+  ...['app.js', 'brand.js', 'bus.js', 'markdown-preview.js', 'chat.js', 'project-archive.js', 'processing.js', 'agents.js', 'federation.js', 'requests.js', 'org-create.js', 'console-restart.js', 'onboarding.js', 'workspace-data.js', 'workspace.js', 'tasks-board.js', 'panes.js'].map(f => ['/' + f, [f, 'text/javascript; charset=utf-8']]),
  ['/files.js', ['files.js', 'text/javascript; charset=utf-8']],
  ['/projects.js', ['projects.js', 'text/javascript; charset=utf-8']],
  ['/projects.css', ['projects.css', 'text/css; charset=utf-8']],
  ['/files.css', ['files.css', 'text/css; charset=utf-8']],
-  ...['shared/app.css', 'tokens.css', 'console.css', 'live.css', 'bus.css', 'shell.css', 'chat.css', 'project-archive.css', 'processing.css', 'org-create.css', 'onboarding.css', 'tasks-board.css'].map(f => ['/' + f, [f, 'text/css; charset=utf-8']]),
+  ...['shared/app.css', 'tokens.css', 'console.css', 'live.css', 'bus.css', 'shell.css', 'chat.css', 'project-archive.css', 'processing.css', 'org-create.css', 'onboarding.css', 'tasks-board.css', 'panes.css'].map(f => ['/' + f, [f, 'text/css; charset=utf-8']]),
  ['/display.js', ['display.js', 'text/javascript; charset=utf-8']],
  ['/inbox.js', ['inbox.js', 'text/javascript; charset=utf-8']],
  ['/inbox.css', ['inbox.css', 'text/css; charset=utf-8']],
@@ -76,6 +77,9 @@ const files = new Map([
  ['/editor.css', ['editor.css', 'text/css; charset=utf-8']],
  ['/icons.svg', ['icons.svg', 'image/svg+xml']],
  ['/project-remote.css', ['project-remote.css', 'text/css; charset=utf-8']],
+  // Phase P2 (#1873): the owner's System types control (dashboard section and project selection).
+  ['/system-types.js', ['system-types.js', 'text/javascript; charset=utf-8']],
+  ['/system-types.css', ['system-types.css', 'text/css; charset=utf-8']],
  ...[400, 500, 600, 700].map(w => [`/assets/fonts/manrope-${w}.woff2`, [`assets/fonts/manrope-${w}.woff2`, 'font/woff2']]),
  ...[400, 500, 700].map(w => [`/assets/fonts/jetbrains-mono-${w}.woff2`, [`assets/fonts/jetbrains-mono-${w}.woff2`, 'font/woff2']]),
 ]);
@@ -507,7 +511,9 @@ const AGENT_ROUTES = {
 };
 // F3: the writes the owner makes on a selected organization's bus from Settings (dev org Console).
 const ORG_OWNER_WRITE = path => path === '/api/settings' || path === '/api/instances' || path === '/api/routes'
-  || Object.hasOwn(SEAT_ROUTES, path) || Object.hasOwn(AGENT_ROUTES, path) || path.startsWith('/api/proxy/');
+  || Object.hasOwn(SEAT_ROUTES, path) || Object.hasOwn(AGENT_ROUTES, path) || path.startsWith('/api/proxy/')
+  // Phase P2 (#1873): the System types enable switch and a project's selection; the route keeps its own checks.
+  || SYSTEM_TYPES_ROUTE.test(path);
 async function agentSend(req, res, { route, agentWrite, preview, log, note = null }) {
  let target = null;
  // The instance or name is quoted and cut short so a crafted value can't forge a log line. A reason is never logged.
@@ -773,7 +779,7 @@ async function libraryStatusRead(res, read, search) {
 // `log` takes one line per send attempt that got past sign-in; never the body. `fieldsFile` is for
 // tests; the field table is otherwise the committed packages/tasks/fields.json.
 // `agentWrite` (row 194, D7) is `(verb, args) => Promise` for the Agents section's verbs and instance.request.
-export async function startServer({ host = '127.0.0.1', port = 7330, board = DEFAULT_BOARD, timeout = 20000, bus = null, reads = null, preview = null, sso = null, tester = false, testerSocket = null, testerAuthHeader = null, proof = null, testerProofHeader = null, send = null, settingsWrite = null, projectFiles = null, projectFile = null, projectSave = null, libraryStatus = null, libraryRevert = null, chat = null, nameWrite = null, assistantStop = null, instancesWrite = null, routesWrite = null, agentWrite = null, proxyCall = null, processing = null, decisionWrite = null, requestRead = null, requestWrite = null, userOptions = null, federation = null, organizations = null, preselect = null, routes = [], orgAdmin = null, devAllowHosts = [], log = line => console.log(line), fieldsFile = undefined, restart = null, trail = null, boot = randomUUID(), workspaceTimeoutMs = undefined, agentLevels = null } = {}) {
+export async function startServer({ host = '127.0.0.1', port = 7330, board = DEFAULT_BOARD, timeout = 20000, bus = null, reads = null, preview = null, sso = null, tester = false, testerSocket = null, testerAuthHeader = null, proof = null, testerProofHeader = null, send = null, settingsWrite = null, projectFiles = null, projectFile = null, projectSave = null, libraryStatus = null, libraryRevert = null, chat = null, nameWrite = null, assistantStop = null, instancesWrite = null, routesWrite = null, agentWrite = null, proxyCall = null, processing = null, decisionWrite = null, requestRead = null, requestWrite = null, systemTypesWrite = null, userOptions = null, federation = null, organizations = null, preselect = null, routes = [], orgAdmin = null, devAllowHosts = [], log = line => console.log(line), fieldsFile = undefined, restart = null, trail = null, boot = randomUUID(), workspaceTimeoutMs = undefined, agentLevels = null } = {}) {
  // org-lan-bind: the dev owner on the LAN is an explicit opt-in. `devAllowHosts` names the Host
  // names (without a port) a remote browser may use; only the dev owner takes them, and only with
  // them may it bind a non-loopback IPv4 address. SSO, preview and tester listeners stay loopback.
@@ -796,6 +802,8 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
  // #797 / #1839 Task 3: the request intake reads need --sso, the writes also --send; never the tester.
  if ((requestRead !== null || requestWrite !== null) && (tester || sso === null || (requestRead !== null && typeof requestRead !== 'function') || (requestWrite !== null && (send === null || typeof requestWrite !== 'function'))))
    throw new Error('Console requests need --sso (and --send for the writes) on the main listener');
+  // Phase P2 (#1873): the owner's System types writes need --sso and --send, never the tester.
+  if (systemTypesWrite !== null && (tester || sso === null || send === null || typeof systemTypesWrite !== 'function')) throw new Error('System types writes need --sso and --send on the main listener');
  const confirmations = createConfirmations();
  const registered = routeTable();
  for (const registerRoutes of routes) registerRoutes(registered);
@@ -818,7 +826,7 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
  // `userOptions` (FED R6, #1800) is `session => options`, the bus-backed options over that session
  // user's own transport (console-bus.mjs). Only a signed-in listener has user sessions.
  if (userOptions !== null && (sso === null || typeof userOptions !== 'function')) throw new Error('user sessions need --sso');
-  const owner = { bus, reads, send, settingsWrite, projectFiles, projectFile, projectSave, libraryStatus, libraryRevert, chat, nameWrite, assistantStop, instancesWrite, routesWrite, agentWrite, proxyCall, processing, decisionWrite, requestRead, requestWrite, upstream, files };
+  const owner = { bus, reads, send, settingsWrite, projectFiles, projectFile, projectSave, libraryStatus, libraryRevert, chat, nameWrite, assistantStop, instancesWrite, routesWrite, agentWrite, proxyCall, processing, decisionWrite, requestRead, requestWrite, systemTypesWrite, upstream, files };
  const hub = federationView(federation);
  // An object with none of the three is refused too: asking for the preview never serves without it.
  if (preview !== null && !(preview = previewOptions({ publicHost: preview.host, authHeader: preview.header, allowUser: preview.user }))) {
@@ -832,7 +840,7 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
  let boundAddress = null, boundPort = null;
  const server = createServer(async (req, res) => {
    // A granted user's request rebinds these below; every other request keeps the owner's.
-    let { bus, reads, send, settingsWrite, projectFiles, projectFile, projectSave, libraryStatus, libraryRevert, chat, nameWrite, assistantStop, instancesWrite, routesWrite, agentWrite, proxyCall, processing, decisionWrite, requestRead, requestWrite, upstream, files } = owner, granted = false, chatGrants = [];
+    let { bus, reads, send, settingsWrite, projectFiles, projectFile, projectSave, libraryStatus, libraryRevert, chat, nameWrite, assistantStop, instancesWrite, routesWrite, agentWrite, proxyCall, processing, decisionWrite, requestRead, requestWrite, systemTypesWrite, upstream, files } = owner, granted = false, chatGrants = [];
    res.setHeader('x-content-type-options', 'nosniff');
    res.setHeader('referrer-policy', 'no-referrer');
    // Under --sso the Sign out form's POST is redirected to the provider's end-session endpoint, and
@@ -902,7 +910,7 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
    // alone stays open on a loopback Host for the status and release gates (Q-C).
    if (sso !== null && !named && !(path === '/healthz' && req.method === 'GET')) return json(res, 403, { error: 'public Host required' });
    // No CORS. JSON content type and same-origin checks keep browser forms out.
-    const decisionPath = DECISION_ROUTE.test(path), requestPath = REQUEST_ROUTE.test(path), remotePath = PROJECT_REMOTE_ROUTE.test(path);
+    const decisionPath = DECISION_ROUTE.test(path), requestPath = REQUEST_ROUTE.test(path), remotePath = PROJECT_REMOTE_ROUTE.test(path), systemTypesPath = SYSTEM_TYPES_ROUTE.test(path);
    if (req.headers.origin && req.headers.origin !== (named ? (sso ? (localOrigin ?? sso.publicOrigin) : `https://${preview.host}`) : `http://${req.headers.host}`))
      return decisionPath ? decisionRefuse(res, 'cross-origin') : requestPath ? requestRefuse(res, 'cross-origin') : json(res, 403, { error: 'cross-origin request refused' });
    let signer = preview, ssoSession = null;
@@ -914,7 +922,7 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
      if (!session && path !== '/healthz') {
        if (decisionPath) return decisionRefuse(res, 'sign-in-required');
        if (requestPath) return requestRefuse(res, 'sign-in-required');
-        if (remotePath) return json(res, 401, { error: 'sign-in-required' });
+        if (remotePath || systemTypesPath) return json(res, 401, { error: 'sign-in-required' });
        if (path.startsWith('/api/') || req.method !== 'GET') return json(res, 401, { error: 'sign-in required' });
        res.writeHead(303, { location: `/auth/login?return=${encodeURIComponent(path + search)}`, 'cache-control': 'no-store' });
        return res.end();
@@ -928,7 +936,7 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
        if (!organizations && !userRoute(path, req.method)) return json(res, 403, { error: 'owner-only', message: 'this part of the Console is the business owner\'s' });
        if (!organizations && userOptions === null) return json(res, 503, { error: 'not-configured', message: 'the Console has no user transport' });
        if (!organizations) ({ bus, send, settingsWrite, projectFiles, projectFile, projectSave, chat, nameWrite, assistantStop, instancesWrite, routesWrite, agentWrite, processing } = userOptions(session));
-        reads = null; upstream = null; libraryStatus = null; libraryRevert = null; files = USER_FILES; granted = true; proxyCall = null;
+        reads = null; upstream = null; libraryStatus = null; libraryRevert = null; files = USER_FILES; granted = true; proxyCall = null; systemTypesWrite = null;
        chatGrants = sso.chatGrants?.(session) ?? [];
      }
    }
@@ -959,7 +967,7 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
      ({ bus = null, reads = null, send = null, settingsWrite = null, projectFiles = null, projectFile = null,
        projectSave = null, libraryStatus = null, libraryRevert = null, chat = null, nameWrite = null,
        assistantStop = null, instancesWrite = null, routesWrite = null, agentWrite = null, proxyCall = null,
-        processing = null, decisionWrite = null, requestRead = null, requestWrite = null, upstream = null } = selected);
+        processing = null, decisionWrite = null, requestRead = null, requestWrite = null, systemTypesWrite = null, upstream = null } = selected);
      }
      // F3: the owner's settings writes reach the selected organization's bus too (limits, routing,
      // agents, assistant, instances, model proxy). The routes below keep their own checks.
@@ -1016,7 +1024,13 @@ export async function startServer({ host = '127.0.0.1', port = 7330, board = DEF
      return projectRemoteHTTP(req, res, { path, read: requestRead, write: send ? requestWrite : null,
        session: ssoSession, live: () => sso.session(req), origin: localOrigin ?? sso.publicOrigin });
    }
-    if (tester && ['/project-remote.js', '/project-remote.css', '/files.js', '/files.css'].includes(path)) return json(res, 403, { error: 'owner-only' });
+    // Phase P2 (#1873): the owner's System types read and writes on the selected organization.
+    if (systemTypesPath) {
+      if (tester || granted || !named || sso === null) return json(res, 403, { error: 'owner-only' });
+      return systemTypesHTTP(req, res, { path, read: requestRead, write: send ? systemTypesWrite : null,
+        session: ssoSession, live: () => sso.session(req), origin: localOrigin ?? sso.publicOrigin });
+    }
+    if (tester && ['/project-remote.js', '/project-remote.css', '/files.js', '/files.css', '/system-types.js', '/system-types.css'].includes(path)) return json(res, 403, { error: 'owner-only' });
    // Row 194 (#1692, D4.1): the tester also launches and terminates.
    if (tester && !['GET', 'HEAD'].includes(req.method) && !['/api/instances', '/api/routes', '/api/name', '/api/agent/launch', '/api/agent/terminate'].includes(path) && !TESTER_CHAT_WRITE.test(path))
      return json(res, 403, { error: 'read-only', sent: false });
@@ -0,0 +1,140 @@
+// Phase P2 (#1873): the owner's System types routes on a selected organization. Owner Console
+// transports only; no caller-supplied business, actor or subject reaches the bus.
+//
+// GET  /api/system-types                    installed modules (label, description) and the enabled set,
+//                                           plus the plugin revision when writes are on
+// POST /api/system-types                    {revision, enabled}: plugins.set {'system-type': enabled},
+//                                           the organization writer's owner fence, revision and receipt
+// GET  /api/system-types/projects/<id>      the same, with the project's selection, active and inactive
+// POST /api/system-types/projects/<id>      {systemTypes}: project.system-types.set
+//
+// `read` is the owner's Console call (consoleCall): it reaches only `system-types.console`, which the
+// broker answers to the business human's console cap. `write` is the owner's human transport limited
+// to SYSTEM_TYPE_VERBS, present only for the owner's own session under --send.
+export const SYSTEM_TYPES_ROUTE = /^\/api\/system-types(?:\/projects\/([^/]+))?$/;
+export const SYSTEM_TYPE_VERBS = Object.freeze(['plugins', 'plugins.set', 'project.system-types.set']);
+const ID = /^[A-Za-z0-9][A-Za-z0-9._-]{0,159}$/;
+// A module name, as plugins/src/kinds.mjs NAME.
+const NAME = /^[a-z][a-z0-9-]{0,63}$/;
+const REVISION = /^[a-f0-9]{64}$/;
+const TRANSACTION = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/;
+const MAX_TYPES = 64;
+const one = (req, key) => req.headersDistinct[key]?.length === 1 ? req.headersDistinct[key][0] : null;
+const codes = {
+  'invalid-request': 400, 'invalid-plugins': 400, 'unknown-plugin': 400, 'system-type-unknown': 400,
+  'project-not-found': 404, 'revision-conflict': 409, 'organization-busy': 409, 'system-type-not-enabled': 409,
+  'human-required': 403, 'organization-system-types-human-only': 403, 'read-only': 403,
+  'not-configured': 503, 'system-type-invalid': 503, 'no-bus-host': 503,
+};
+function json(res, status, value) {
+  res.writeHead(status, { 'content-type': 'application/json', 'cache-control': 'no-store' });
+  res.end(JSON.stringify(value));
+}
+const names = list => Array.isArray(list) && list.length <= MAX_TYPES && list.every(x => typeof x === 'string' && NAME.test(x)) && new Set(list).size === list.length;
+const text = value => typeof value === 'string' && value.trim() !== '' && value.length <= 400 && !/[\r\n]/.test(value);
+function consoleShape(result, project) {
+  if (!result || !Array.isArray(result.installed) || !names(result.enabled)) return null;
+  const installed = [];
+  for (const m of result.installed) {
+    if (!m || !NAME.test(m.id ?? '') || !text(m.label) || !text(m.description)) return null;
+    installed.push({ id: m.id, label: m.label, description: m.description });
+  }
+  if (new Set(installed.map(m => m.id)).size !== installed.length) return null;
+  let selection = null;
+  if (project !== null) {
+    const p = result.project;
+    if (!p || p.project !== project || !names(p.selected) || !names(p.active) || !names(p.inactive)) return null;
+    selection = { project, selected: p.selected, active: p.active, inactive: p.inactive };
+  } else if (result.project !== null) return null;
+  return { installed, enabled: result.enabled, project: selection };
+}
+const selectionShape = (r, project) => r && r.project === project && names(r.selected) && names(r.active) && names(r.inactive)
+  ? { project, selected: r.selected, active: r.active, inactive: r.inactive } : null;
+
+async function body(req, keys) {
+  if (one(req, 'content-type')?.split(';')[0].trim().toLowerCase() !== 'application/json') return null;
+  const chunks = []; let size = 0;
+  for await (const chunk of req) { size += chunk.length; if (size > 4096) return 'too-large'; chunks.push(chunk); }
+  let value;
+  try { value = JSON.parse(Buffer.concat(chunks).toString('utf8')); } catch { return null; }
+  if (!value || typeof value !== 'object' || Array.isArray(value) || Object.keys(value).length !== keys.length || !keys.every(k => Object.hasOwn(value, k))) return null;
+  return value;
+}
+
+export async function systemTypesHTTP(req, res, { path, read, write, session, live, origin }) {
+  const refuse = (status, error) => json(res, status, { error });
+  const fail = error => { const code = codes[error?.code] ? error.code : 'outcome-unknown'; return refuse(codes[code] ?? 503, code); };
+  if (!['GET', 'POST'].includes(req.method)) return refuse(405, 'method-not-allowed');
+  if (!session) return refuse(401, 'sign-in-required');
+  if (!read) return refuse(503, 'not-configured');
+  if (req.method === 'POST' && !write) return refuse(403, 'read-only');
+  const site = one(req, 'sec-fetch-site'), from = one(req, 'origin');
+  if (req.method === 'POST' ? from !== origin || site !== 'same-origin'
+    : (req.headersDistinct.origin && from !== origin) || (req.headersDistinct['sec-fetch-site'] && !['same-origin', 'none'].includes(site)))
+    return refuse(403, 'cross-origin');
+  let project = null;
+  const match = SYSTEM_TYPES_ROUTE.exec(path);
+  if (match?.[1] !== undefined) {
+    try { project = decodeURIComponent(match[1]); } catch { return refuse(404, 'project-not-found'); }
+    if (!ID.test(project)) return refuse(404, 'project-not-found');
+  }
+  let args = null;
+  if (req.method === 'POST') {
+    const value = await body(req, project === null ? ['revision', 'enabled'] : ['systemTypes']);
+    if (value === 'too-large') return refuse(413, 'invalid-request');
+    if (!value) return refuse(400, 'invalid-request');
+    if (project === null ? typeof value.revision !== 'string' || !REVISION.test(value.revision) || !names(value.enabled) : !names(value.systemTypes))
+      return refuse(400, 'invalid-request');
+    args = value;
+  }
+  if (live() !== session) return refuse(401, 'sign-in-required');
+  const subject = { provider: session.provider, iss: session.iss, sub: session.sub };
+  // The read comes first on every request: a write names only modules this organization has installed.
+  let current;
+  try { current = consoleShape(await read('system-types.console', project === null ? {} : { project }, { subject }), project); }
+  catch (error) { return fail(error); }
+  if (!current) return refuse(503, 'outcome-unknown');
+  const installed = new Set(current.installed.map(m => m.id));
+
+  if (req.method === 'GET') {
+    let revision = null;
+    if (write && project === null) {
+      // The enabled set and its revision come from one plugins read. The page sends back a whole
+      // replacement list, so a list older than its revision would undo a change made in between.
+      let plugins;
+      try { plugins = await write('plugins', {}); } catch (error) { return fail(error); }
+      revision = plugins?.revision ?? null;
+      const enabled = plugins?.plugins?.['system-type'] ?? [];
+      if (!REVISION.test(revision ?? '') || !names(enabled)) return refuse(503, 'outcome-unknown');
+      current.enabled = enabled;
+    }
+    if (live() !== session) return refuse(401, 'sign-in-required');
+    return json(res, 200, { ...current, writable: Boolean(write), ...(project === null && write ? { revision } : {}) });
+  }
+
+  // The session is checked again after the read: a sign-out while it ran dispatches no write.
+  if (live() !== session) return refuse(401, 'sign-in-required');
+
+  if (project === null) {
+    if (args.enabled.some(id => !installed.has(id))) return refuse(400, 'system-type-unknown');
+    let result;
+    try { result = await write('plugins.set', { revision: args.revision, plugins: { 'system-type': args.enabled } }); }
+    catch (error) { return fail(error); }
+    // A write admitted at spawn may already have committed: its receipt is returned even if the
+    // session ended meanwhile, never reported as not done.
+    const enabled = result?.plugins?.['system-type'] ?? [];
+    if (!result || !REVISION.test(result.revision ?? '') || !TRANSACTION.test(result.transaction ?? '') || !names(enabled)
+      || JSON.stringify(enabled) !== JSON.stringify(args.enabled))
+      return refuse(503, 'outcome-unknown');
+    return json(res, 200, { enabled, revision: result.revision, transaction: result.transaction });
+  }
+
+  // The broker refuses a type the organization has not enabled (system-type-not-enabled); a type that
+  // is not installed is refused here first.
+  if (args.systemTypes.some(id => !installed.has(id))) return refuse(400, 'system-type-unknown');
+  let result;
+  try { result = selectionShape(await write('project.system-types.set', { project, systemTypes: args.systemTypes }), project); }
+  catch (error) { return fail(error); }
+  if (!result || JSON.stringify(result.selected) !== JSON.stringify(args.systemTypes)) return refuse(503, 'outcome-unknown');
+  return json(res, 200, result);
+}
@@ -18,8 +18,8 @@ test('served Console browser: real board fixtures, keyboard, drafts, receipts, t
    assert.equal(await b.evaluate('document.querySelector("#session-count").textContent'), '3 of 4');
    await b.evaluate('document.querySelector("#hide-offline").click()');
    assert.equal(await b.evaluate('document.querySelectorAll("table.sessions tbody tr").length'), 4);
-    // Rows 129, 154, 191, 194 and 294: chat.js, editor.js, processing.js, agents.js and federation.js are the scripts added, and #1839 adds requests.js (the intake panel under an owner's chat message), all same origin; the list is the pin, so another script is a visible change. #797 adds project-archive.js immediately after chat.js. F2 adds onboarding.js after org-create.js, and F3 adds console-restart.js after it. U2 (#1873) adds workspace-data.js and workspace.js before console-restart.js, and U4b adds tasks-board.js after workspace.js.
-    assert.deepEqual(await b.evaluate('[...document.querySelectorAll("script")].map(s => s.getAttribute("src"))'), ['/editor.js', '/processing.js', '/org-create.js', '/onboarding.js', '/workspace-data.js', '/workspace.js', '/tasks-board.js', '/console-restart.js', '/display.js', '/inbox.js', '/files.js', '/project-remote.js', '/federation.js', '/brand.js', '/app.js', '/markdown-preview.js', '/projects.js', '/chat.js', '/project-archive.js', '/agents.js', '/bus.js', '/requests.js']);
+    // Rows 129, 154, 191, 194 and 294: chat.js, editor.js, processing.js, agents.js and federation.js are the scripts added, and #1839 adds requests.js (the intake panel under an owner's chat message), all same origin; the list is the pin, so another script is a visible change. #797 adds project-archive.js immediately after chat.js. F2 adds onboarding.js after org-create.js, and F3 adds console-restart.js after it. U2 (#1873) adds workspace-data.js and workspace.js before console-restart.js, and U4b adds tasks-board.js after workspace.js. U5 (#1873) adds panes.js (Side by side) just before bus.js, which mounts it. P2 (#1873) adds system-types.js after project-remote.js.
+    assert.deepEqual(await b.evaluate('[...document.querySelectorAll("script")].map(s => s.getAttribute("src"))'), ['/editor.js', '/processing.js', '/org-create.js', '/onboarding.js', '/workspace-data.js', '/workspace.js', '/tasks-board.js', '/console-restart.js', '/display.js', '/inbox.js', '/files.js', '/project-remote.js', '/system-types.js', '/federation.js', '/brand.js', '/app.js', '/markdown-preview.js', '/projects.js', '/chat.js', '/project-archive.js', '/agents.js', '/panes.js', '/bus.js', '/requests.js']);
    assert.equal(await b.evaluate(`document.querySelectorAll('script[src="/processing.js"]').length`), 1);
    assert.equal(await b.evaluate(`document.querySelectorAll('script[src="/chat.js"]').length`), 1);
    assert.equal(await b.evaluate('!!window.injected'), false);
@@ -0,0 +1,42 @@
+import { createHash, randomUUID } from 'node:crypto';
+import { installedSystemTypes } from '../../../plugins/src/system-types.mjs';
+
+// Phase P2 (#1873): a per-organization stand-in for the two transports the System types routes use,
+// shaped as the broker answers them. `requestRead` answers system-types.console with the installed
+// modules (the plug-in data itself, read from packages/plugins), the enabled set and a project's
+// selection. `systemTypesWrite` answers plugins, plugins.set (revision checked, a transaction
+// returned) and project.system-types.set (enabled types only). `owner: false` makes plugins.set
+// refuse as the organization writer's owner fence does for anyone but the human.
+export async function systemTypesFake({ enabled = [], projects = {}, owner = true } = {}) {
+  const installed = await installedSystemTypes();
+  const state = { enabled: [...enabled], projects: structuredClone(projects), n: 0, writes: [] };
+  const revision = () => createHash('sha256').update(`system-types-${state.n}`).digest('hex');
+  const fail = code => { throw Object.assign(new Error(code), { code }); };
+  const selection = project => {
+    const selected = state.projects[project];
+    return { project, selected: [...selected], active: selected.filter(x => state.enabled.includes(x)), inactive: selected.filter(x => !state.enabled.includes(x)) };
+  };
+  const requestRead = async (verb, args) => {
+    if (verb !== 'system-types.console') fail('invalid-request');
+    if (args.project !== undefined && !Object.hasOwn(state.projects, args.project)) fail('project-not-found');
+    return { installed: structuredClone(installed), enabled: [...state.enabled], project: args.project === undefined ? null : selection(args.project) };
+  };
+  const systemTypesWrite = async (verb, args) => {
+    state.writes.push(verb);
+    if (verb === 'plugins') return { business: 'fake', revision: revision(), plugins: { 'system-type': [...state.enabled] } };
+    if (verb === 'plugins.set') {
+      if (args.revision !== revision()) fail('revision-conflict');
+      if (!owner) fail('organization-system-types-human-only');
+      state.enabled = [...args.plugins['system-type']]; state.n++;
+      return { business: 'fake', revision: revision(), plugins: { 'system-type': [...state.enabled] }, transaction: randomUUID() };
+    }
+    if (verb === 'project.system-types.set') {
+      if (!Object.hasOwn(state.projects, args.project)) fail('project-not-found');
+      if (args.systemTypes.some(x => !state.enabled.includes(x))) fail('system-type-not-enabled');
+      state.projects[args.project] = [...args.systemTypes];
+      return selection(args.project);
+    }
+    fail('invalid-request');
+  };
+  return { requestRead, systemTypesWrite, state, installed };
+}
@@ -0,0 +1,340 @@
+// U5 (#1873, sample 07): Side by side shows two panes, each holding one page of any organization.
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { startServer } from '../src/serve.mjs';
+import { createDevOwner } from '../src/dev-owner.mjs';
+import { browser } from './browser.mjs';
+import { close } from './fixture.mjs';
+
+const waitFor = b => expression => b.evaluate(`(async()=>{for(let i=0;i<200;i++){if(${expression})return;await new Promise(r=>setTimeout(r,30))}throw Error(${JSON.stringify(expression)})})()`);
+
+// Three organizations: two running buses and one stopped (home). `state.flip` changes what the
+// running organizations report, so a refresh repaints both panes.
+function orgs(state = { flip: false, seen: [] }) {
+  const ORGS = [
+    { id: 'ddigital', label: 'Distinctly Digital', theme: 'rosewood', busHealthy: true },
+    { id: 'forge', label: 'Forge', theme: 'cobalt', busHealthy: true },
+    { id: 'home', label: 'Home', theme: 'grove', busHealthy: false },
+  ];
+  const PROJECTS = { ddigital: [{ id: 'spring-launch', name: 'Spring launch' }, { id: 'brand-refresh', name: 'Brand refresh' }], forge: [{ id: 'api-gateway', name: 'API gateway' }], home: [] };
+  const INSTANCES = { ddigital: ['chief', 'copywriter', 'producer', 'editor', 'researcher', 'designer', 'analyst', 'scheduler'], forge: ['chief', 'builder', 'tester', 'reviewer', 'operator', 'scribe'] };
+  const THREADS = { ddigital: [{ id: 't0', name: 'Kickoff notes', project: 'spring-launch', instance: 'chief' }, { id: 't1', name: 'Launch email', project: 'spring-launch', instance: 'copywriter' }], forge: [{ id: 'f0', name: 'Gateway auth', project: 'api-gateway', instance: 'chief' }] };
+  const instances = id => ({ business: id, revision: 'a'.repeat(64), launch: true, noHire: [], retired: [], definitions: {},
+    instances: Object.fromEntries(INSTANCES[id].map((n, i) => [n, { definition: n, vars: {}, launched: true, launcher: false, protected: false, kept: false, running: [`r${i}`], alive: [] }])) });
+  const agents = id => INSTANCES[id].map((role, i) => ({ role, holder_run: `r${i}`, state: (i % 2 === 0) === state.flip ? 'working' : 'waiting' }));
+  const business = id => ({ business: { id, human: 'jason', arbiters: ['chief'], projects: PROJECTS[id].map(p => p.id), vars: {}, instances: INSTANCES[id].map(n => ({ instance: n, vars: {} })), appearance: { theme: ORGS.find(o => o.id === id).theme } } });
+  return {
+    list: async () => ORGS,
+    resolve: async id => {
+      state.seen.push(id);
+      const org = ORGS.find(o => o.id === id); if (!org) return null;
+      if (!org.busHealthy) return { busHealthy: false, reads: null, bus: {}, chat: { projects: async () => [], threads: async () => [] } };
+      return {
+        busHealthy: true,
+        reads: { business: async () => business(id), settings: async () => ({ release: '0.0.42', launch: { limits: { total: 4 } } }), queue: async () => ({ rows: [] }), busStatus: async () => ({}) },
+        bus: { instances: async () => instances(id), messages: async () => ({ messages: [], unread: 0 }), agents: async () => agents(id), 'thread.claims': async () => [], inbox: async () => [], tasks: async () => [] },
+        chat: { projects: async () => PROJECTS[id], threads: async () => THREADS[id] },
+        projectFiles: async () => ({ head: 'a'.repeat(40), files: [] }),
+      };
+    },
+  };
+}
+
+async function open(t, { width = 1440, height = 900, hash = '#/orgs/ddigital/side-by-side', state } = {}) {
+  const server = await startServer({ port: 0, sso: createDevOwner(), organizations: orgs(state), log: () => {} }); t.after(() => close(server));
+  const b = await browser({ machine: false }); t.after(() => b.close());
+  await b.viewport(width, height);
+  const base = `http://127.0.0.1:${server.address().port}/`;
+  await b.navigate(base + hash);
+  return { b, base, wait: waitFor(b) };
+}
+const text = key => `(document.querySelector("#pane-${key} [data-pane-body]")?.innerText || "")`;
+const title = key => `(document.querySelector("#pane-${key} [data-pane-ttl]")?.textContent || "")`;
+const query = '(() => Object.fromEntries(new URLSearchParams(location.hash.split("?")[1] || "")))()';
+const pick = (b, key, value) => b.evaluate(`(() => { const s = document.querySelector("#pane-${key}-pick"); s.value = ${JSON.stringify(value)}; if (s.value !== ${JSON.stringify(value)}) throw Error("no option " + ${JSON.stringify(value)}); s.dispatchEvent(new Event("change", { bubbles: true })); })()`);
+
+test('the Side by side nav item opens two panes with different organizations, and the URL restores both after a reload', async t => {
+  const state = { flip: false, seen: [] };
+  const { b, base, wait } = await open(t, { hash: '#/orgs/ddigital/organization', state });
+  await wait('document.querySelector("[data-org-dashboard]")');
+  await b.evaluate('[...document.querySelectorAll("#sections > li > a")].find(a => a.textContent.trim() === "Side by side").click()');
+  await wait(`document.querySelectorAll(".panes > .pane:not([hidden])").length === 2 && ${title('a')}.includes("Distinctly Digital") && ${title('b')}.includes("Forge")`);
+  assert.doesNotMatch(await b.evaluate('document.getElementById("bus-view").innerText'), /Side by side is not built yet/i);
+  assert.equal(await b.evaluate('document.querySelector("#bus-view h1").textContent'), 'Side by side');
+  assert.equal(await b.evaluate('document.title'), 'Side by side · Mosaic Console');
+  assert.deepEqual(await b.evaluate(query), { a: 'ddigital/organization', b: 'forge/organization', w: '50', show: 'a' });
+  await wait(`${text('a')}.includes("Distinctly Digital") && ${text('b')}.includes("Forge")`);
+  // Each pane's links name its own organization.
+  assert.equal(await b.evaluate('[...document.querySelectorAll("#pane-b [data-pane-body] a[href^=\\"#/\\"]")].every(a => a.getAttribute("href").startsWith("#/orgs/forge/"))'), true);
+  assert.equal(await b.evaluate('document.querySelectorAll("#pane-a [data-pane-body] h1[aria-level=\\"2\\"]").length > 0'), true);
+  // The picker lists every organization and its projects.
+  const groups = await b.evaluate('[...document.querySelectorAll("#pane-b-pick optgroup")].map(g => g.label)');
+  assert.deepEqual(groups, ['Distinctly Digital', 'Forge', 'Home · bus unavailable']);
+  assert.deepEqual(await b.evaluate('[...document.querySelectorAll("#pane-b-pick option")].map(o => o.value).filter(Boolean)'),
+    ['ddigital/organization', 'ddigital/agents', 'ddigital/projects/spring-launch', 'ddigital/projects/brand-refresh', 'forge/organization', 'forge/agents', 'forge/projects/api-gateway', 'home/organization', 'home/agents']);
+  // Pick a project in the right pane; the left keeps its page.
+  await pick(b, 'b', 'forge/projects/api-gateway');
+  await wait(`${title('b')}.startsWith("API gateway") && ${text('b')}.includes("API gateway") && location.hash.includes("b=forge/projects/api-gateway")`);
+  assert.match(await b.evaluate(title('a')), /^Dashboard/);
+  // A project tab opens in the pane, not the full view.
+  await b.evaluate('[...document.querySelectorAll("#pane-b nav.project-tabs a")].find(a => /Tasks/.test(a.textContent)).click()');
+  await wait(`location.hash.includes("b=forge/projects/api-gateway/tasks") && ${title('b')}.includes("Tasks")`);
+  assert.match(await b.evaluate('location.hash'), /^#\/orgs\/ddigital\/side-by-side\?/);
+  // Reload: both panes come back from the URL.
+  await b.call('Page.reload');
+  await wait('document.readyState === "complete"');
+  await wait(`${title('a')}.startsWith("Dashboard") && ${title('a')}.includes("Distinctly Digital") && ${title('b')}.includes("API gateway") && ${title('b')}.includes("Tasks")`);
+  assert.deepEqual(await b.evaluate(query), { a: 'ddigital/organization', b: 'forge/projects/api-gateway/tasks', w: '50', show: 'a' });
+  // A shared link opens exactly what it names, whatever this browser remembered.
+  await b.navigate(`${base}#/orgs/forge/side-by-side?a=forge/agents&b=ddigital/projects/spring-launch&w=40&show=b`);
+  await wait(`${title('a')}.startsWith("Agents") && ${title('a')}.includes("Forge") && ${title('b')}.startsWith("Spring launch")`);
+  assert.equal(await b.evaluate('document.querySelector("[data-sbs-divider]").getAttribute("aria-valuenow")'), '40');
+  // A link with a route a pane does not draw falls back to the remembered layout or the default.
+  await b.navigate(`${base}#/orgs/ddigital/side-by-side?a=ddigital/settings&b=nope!/organization`);
+  await wait(`document.querySelectorAll(".panes > .pane:not([hidden])").length === 2 && ${title('a')}.length > 0 && !location.hash.includes("settings")`);
+  // Leaving the page stops both panes reading.
+  await b.evaluate('location.hash = "#/orgs/ddigital/agents"');
+  await wait('!document.querySelector("[data-side-by-side]") && [...document.querySelectorAll("#bus-view h1")].some(h => h.textContent.trim() === "Agents")');
+  assert.ok(state.seen.includes('forge') && state.seen.includes('ddigital'));
+});
+
+test('the divider resizes the panes by mouse and by keyboard', async t => {
+  const { b, wait } = await open(t);
+  await wait(`${title('a')}.length > 0 && ${title('b')}.length > 0`);
+  const sep = '[role=separator][data-sbs-divider]';
+  assert.deepEqual(await b.evaluate(`(() => { const d = document.querySelector("${sep}"); return [d.getAttribute("aria-valuenow"), d.getAttribute("aria-valuemin"), d.getAttribute("aria-valuemax"), d.getAttribute("aria-orientation"), d.tabIndex]; })()`), ['50', '25', '75', 'vertical', 0]);
+  const ratio = `(() => { const a = document.getElementById("pane-a").getBoundingClientRect().width, b = document.getElementById("pane-b").getBoundingClientRect().width; return Math.round(a / (a + b) * 100); })()`;
+  // Mouse: drag the divider to 30% of the panes' width.
+  const box = await b.evaluate(`(() => { const p = document.querySelector("[data-sbs-panes]").getBoundingClientRect(), d = document.querySelector("${sep}").getBoundingClientRect(); return { left: p.left, width: p.width, x: d.left + d.width / 2, y: d.top + 200 }; })()`);
+  const target = box.left + box.width * 0.3;
+  await b.call('Input.dispatchMouseEvent', { type: 'mouseMoved', x: box.x, y: box.y });
+  await b.call('Input.dispatchMouseEvent', { type: 'mousePressed', x: box.x, y: box.y, button: 'left', buttons: 1, clickCount: 1 });
+  for (const step of [0.25, 0.5, 0.75, 1]) await b.call('Input.dispatchMouseEvent', { type: 'mouseMoved', x: box.x + (target - box.x) * step, y: box.y, button: 'left', buttons: 1 });
+  await b.call('Input.dispatchMouseEvent', { type: 'mouseReleased', x: target, y: box.y, button: 'left', buttons: 0, clickCount: 1 });
+  await wait(`document.querySelector("${sep}").getAttribute("aria-valuenow") === "30" && location.hash.includes("w=30")`);
+  assert.ok(Math.abs(await b.evaluate(ratio) - 30) <= 1);
+  // Keyboard: the separator has focus after the drag; arrows step by 5, Home and End reach the limits.
+  assert.equal(await b.evaluate('document.activeElement.getAttribute("role")'), 'separator');
+  await b.call('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowRight', code: 'ArrowRight', windowsVirtualKeyCode: 39 });
+  await b.call('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowRight', code: 'ArrowRight', windowsVirtualKeyCode: 39 });
+  await wait(`document.querySelector("${sep}").getAttribute("aria-valuenow") === "35"`);
+  await b.call('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
+  await b.call('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
+  await b.call('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
+  await b.call('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
+  await wait(`document.querySelector("${sep}").getAttribute("aria-valuenow") === "25"`);
+  await b.call('Input.dispatchKeyEvent', { type: 'keyDown', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
+  await b.call('Input.dispatchKeyEvent', { type: 'keyUp', key: 'ArrowLeft', code: 'ArrowLeft', windowsVirtualKeyCode: 37 });
+  assert.equal(await b.evaluate(`document.querySelector("${sep}").getAttribute("aria-valuenow")`), '25');
+  await b.call('Input.dispatchKeyEvent', { type: 'keyDown', key: 'End', code: 'End', windowsVirtualKeyCode: 35 });
+  await b.call('Input.dispatchKeyEvent', { type: 'keyUp', key: 'End', code: 'End', windowsVirtualKeyCode: 35 });
+  await wait(`document.querySelector("${sep}").getAttribute("aria-valuenow") === "75" && location.hash.includes("w=75")`);
+  assert.ok(Math.abs(await b.evaluate(ratio) - 75) <= 1);
+  // Closing a pane goes back to one; the divider leaves with it. Add pane brings a second back.
+  await b.evaluate('document.querySelector("#pane-a [data-pane-close]").click()');
+  await wait(`document.getElementById("pane-b").hidden && document.querySelector("${sep}").hidden && !new URLSearchParams(location.hash.split("?")[1]).has("b") && ${title('a')}.includes("Forge")`);
+  assert.equal(await b.evaluate('document.activeElement.id'), 'pane-a-pick');
+  assert.equal(await b.evaluate('document.querySelector("#pane-a [data-pane-close]").hidden'), true);
+  assert.match(await b.evaluate('document.querySelector("[data-sbs-note]").textContent'), /^1 pane ·/);
+  await b.evaluate('document.querySelector("[data-pane-add]").click()');
+  await wait(`!document.getElementById("pane-b").hidden && ${title('b')}.length > 0 && new URLSearchParams(location.hash.split("?")[1]).has("b")`);
+  assert.equal(await b.evaluate('document.querySelector("[data-pane-add]").disabled'), true);
+});
+
+test('each pane keeps its own focus and scroll through a refresh', async t => {
+  const state = { flip: false, seen: [] };
+  const { b, wait } = await open(t, { height: 520, state, hash: '#/orgs/ddigital/side-by-side?a=ddigital/agents&b=forge/agents' });
+  await wait(`${text('a')}.includes("copywriter") && ${text('b')}.includes("builder")`);
+  const scrollable = await b.evaluate('[...document.querySelectorAll("[data-pane-body]")].map(el => el.scrollHeight - el.clientHeight)');
+  assert.ok(scrollable.every(n => n > 60), `both panes scroll: ${scrollable}`);
+  const focused = await b.evaluate('(() => { const a = document.querySelector("#pane-a [data-pane-body] a[href]"); a.focus(); return a.getAttribute("href"); })()');
+  await b.evaluate('document.querySelector("#pane-a [data-pane-body]").scrollTop = 40; document.querySelector("#pane-b [data-pane-body]").scrollTop = 60;');
+  const before = await b.evaluate(`[${text('a')}, ${text('b')}]`);
+  state.flip = true;
+  await b.evaluate('document.getElementById("refresh").click()');
+  await wait(`${text('a')} !== ${JSON.stringify(before[0])} && ${text('b')} !== ${JSON.stringify(before[1])}`);
+  assert.equal(await b.evaluate('document.querySelector("#pane-a").contains(document.activeElement) && document.activeElement.getAttribute("href")'), focused);
+  assert.deepEqual(await b.evaluate('[...document.querySelectorAll("[data-pane-body]")].map(el => el.scrollTop)'), [40, 60]);
+  // Focus in the right pane stays there while the left repaints.
+  const right = await b.evaluate('(() => { const a = document.querySelector("#pane-b [data-pane-body] a[href]"); a.focus({ preventScroll: true }); return a.getAttribute("href"); })()');
+  state.flip = false;
+  await b.evaluate('document.getElementById("refresh").click()');
+  await wait(`${text('a')} === ${JSON.stringify(before[0])}`);
+  assert.equal(await b.evaluate('document.querySelector("#pane-b").contains(document.activeElement) && document.activeElement.getAttribute("href")'), right);
+  assert.deepEqual(await b.evaluate('[...document.querySelectorAll("[data-pane-body]")].map(el => el.scrollTop)'), [40, 60]);
+});
+
+test('a pane whose organization is down shows its state and the other pane still works', async t => {
+  const { b, wait } = await open(t, { hash: '#/orgs/ddigital/side-by-side?a=home/organization&b=forge/organization' });
+  await wait(`${title('a')}.includes("Home") && ${title('b')}.includes("Forge") && ${text('b')}.includes("Forge")`);
+  await wait('/Home: bus unavailable/.test(document.querySelector("#pane-a [data-pane-line]").textContent)');
+  assert.equal(await b.evaluate('document.querySelector("#pane-a [data-pane-line]").getAttribute("role")'), 'status');
+  assert.equal(await b.evaluate('document.querySelector("#pane-a [data-pane-state]").innerText.trim().length > 0'), true);
+  assert.equal(await b.evaluate('document.querySelector("#pane-b [data-pane-line]").hidden'), true);
+  await pick(b, 'b', 'forge/agents');
+  await wait(`${title('b')}.startsWith("Agents") && ${text('b')}.includes("builder")`);
+  await pick(b, 'b', 'forge/projects/api-gateway');
+  await wait(`${title('b')}.startsWith("API gateway") && ${text('b')}.includes("API gateway")`);
+  assert.match(await b.evaluate(title('a')), /Home/);
+  // An organization that is not on the list is one honest line; nothing is read for it.
+  await b.evaluate('location.hash = "#/orgs/ddigital/side-by-side?a=ghost/organization&b=forge/agents"');
+  await wait(`/ghost is not on your organization list/.test(document.querySelector("#pane-a [data-pane-line]").textContent) && ${text('b')}.includes("builder")`);
+});
+
+test('on a phone one pane shows at a time, switched from the bar, with no horizontal scroll', async t => {
+  const { b, wait } = await open(t, { width: 390, height: 844 });
+  await wait(`${title('a')}.length > 0 && ${title('b')}.length > 0 && ${text('a')}.length > 0`);
+  const visible = '[...document.querySelectorAll(".panes > .pane")].filter(p => p.getBoundingClientRect().height > 0).map(p => p.id)';
+  assert.deepEqual(await b.evaluate(visible), ['pane-a']);
+  assert.notEqual(await b.evaluate('getComputedStyle(document.querySelector("[data-sbs-tabs]")).display'), 'none');
+  assert.equal(await b.evaluate('getComputedStyle(document.querySelector("[data-sbs-divider]")).display'), 'none');
+  assert.equal(await b.evaluate('getComputedStyle(document.querySelector("[data-pane-add]")).display'), 'none');
+  assert.deepEqual(await b.evaluate('[...document.querySelectorAll("[data-sbs-tabs] button")].map(x => x.getAttribute("aria-pressed"))'), ['true', 'false']);
+  assert.ok(await b.evaluate('document.documentElement.scrollWidth <= innerWidth'), 'no horizontal scroll');
+  await b.evaluate('document.querySelector("[data-sbs-tabs] [data-pane-show=b]").click()');
+  await wait(`JSON.stringify(${visible}) === '["pane-b"]' && location.hash.includes("show=b")`);
+  assert.deepEqual(await b.evaluate('[...document.querySelectorAll("[data-sbs-tabs] button")].map(x => x.getAttribute("aria-pressed"))'), ['false', 'true']);
+  assert.ok(await b.evaluate('document.documentElement.scrollWidth <= innerWidth'), 'no horizontal scroll on the second pane');
+  await pick(b, 'b', 'ddigital/projects/spring-launch');
+  await wait(`${text('b')}.includes("Spring launch")`);
+  assert.ok(await b.evaluate('document.documentElement.scrollWidth <= innerWidth'), 'no horizontal scroll on a project page');
+});
+
+// Review fixes (#1873 U5 review, findings 1-4). `hold(url)` makes the page's next read of that URL
+// wait until `release()`; the test then changes the pane while the read is pending.
+const hold = url => `(() => { const real = window.fetch; window.held = { url: ${JSON.stringify(url)}, pending: false };
+  window.fetch = async (u, o) => { if (window.held?.url === u && !window.held.done) { window.held.pending = true; await new Promise(r => { window.held.release = () => { window.held.done = true; r(); }; }); } return real(u, o); }; })()`;
+const settled = b => b.evaluate('new Promise(r => setTimeout(r, 400))');
+
+test('a pane closed and opened again rewrites new links for its current organization only', async t => {
+  const { b, wait } = await open(t);
+  await wait(`${title('b')}.includes("Forge") && document.querySelector("#pane-b-pick")?.options.length > 4`);
+  await b.evaluate('document.querySelector("#pane-b [data-pane-close]").click()');
+  await wait('document.querySelector("#pane-b").hidden && !document.querySelector("[data-pane-add]").disabled');
+  await b.evaluate('document.querySelector("[data-pane-add]").click()');
+  await wait(`!document.querySelector("#pane-b").hidden && ${title('b')}.length > 0`);
+  await pick(b, 'b', 'ddigital/organization');
+  await wait(`${title('b')}.includes("Distinctly Digital") && location.hash.includes("b=ddigital/organization")`);
+  // Content a page appends after its own reads (projects.js does this) gets the pane's organization.
+  await b.evaluate(`document.querySelector("#pane-b [data-pane-body]").insertAdjacentHTML("beforeend", '<a data-late href="#/docs/example">late</a><a data-late-api href="/api/files/x">file</a>')`);
+  await wait('document.querySelector("#pane-b [data-late]").getAttribute("href").startsWith("#/orgs/")');
+  assert.equal(await b.evaluate('document.querySelector("#pane-b [data-late]").getAttribute("href")'), '#/orgs/ddigital/docs/example');
+  assert.equal(await b.evaluate('document.querySelector("#pane-b [data-late-api]").getAttribute("href")'), '/api/orgs/ddigital/files/x');
+  // Leaving the page stops every pane observer: later content in the old element is left alone.
+  await b.evaluate('location.hash = "#/orgs/ddigital/agents"');
+  await wait('!document.querySelector("[data-side-by-side]")');
+});
+
+test('a slow project read never paints over the page or organization chosen since', async t => {
+  const { b, wait } = await open(t);
+  await wait(`${title('b')}.includes("Forge") && document.querySelector("#pane-b-pick")?.options.length > 4`);
+  // Page change while the project's thread read is pending.
+  await b.evaluate(hold('/api/orgs/forge/chat/threads'));
+  await pick(b, 'b', 'forge/projects/api-gateway');
+  await wait('window.held.pending');
+  await pick(b, 'b', 'forge/agents');
+  await wait(`${title('b')}.startsWith("Agents") && ${text('b')}.includes("builder")`);
+  await b.evaluate('window.held.release()');
+  await settled(b);
+  assert.equal(await b.evaluate(`${text('b')}.includes("API gateway")`), false, 'the old project did not replace Agents');
+  assert.match(await b.evaluate(title('b')), /^Agents/);
+  // Organization change while the read is pending: the old organization's project is not painted.
+  await b.evaluate(hold('/api/orgs/forge/chat/threads'));
+  await pick(b, 'b', 'forge/projects/api-gateway');
+  await wait('window.held.pending');
+  await pick(b, 'b', 'ddigital/projects/spring-launch');
+  await wait(`${title('b')}.startsWith("Spring launch") && ${text('b')}.includes("Spring launch")`);
+  await b.evaluate('window.held.release()');
+  await settled(b);
+  assert.equal(await b.evaluate(`${text('b')}.includes("API gateway")`), false, 'the old organization did not replace Spring launch');
+  assert.equal(await b.evaluate('[...document.querySelectorAll("#pane-b [data-pane-body] a[href^=\\"#/orgs/\\"]")].every(a => a.getAttribute("href").startsWith("#/orgs/ddigital/"))'), true);
+});
+
+test('the same project in both panes keeps a request choice per pane', async t => {
+  const { b, wait } = await open(t);
+  await wait(`${title('b')}.includes("Forge")`);
+  const { stub, P } = await import('./helpers/projects-review-fixture.mjs');
+  // The fixture answers the project reads of both organizations; the organization list stays real.
+  await b.evaluate(stub.replace('const path=String(url),method', `if(url==='/api/orgs'||url==='/api/themes')return real(url,init);const path=String(url).replace(/^\\/api\\/orgs\\/(?:ddigital|forge)\\//,'/api/'),method`));
+  await b.evaluate('window.MosaicPanes.refresh()');
+  await wait(`document.querySelector('#pane-a-pick option[value="ddigital/projects/${P}"]')`);
+  await b.evaluate(`location.hash = '#/orgs/ddigital/side-by-side?a=ddigital/projects/${P}/requirements&b=forge/projects/${P}/requirements'`);
+  const values = `[...document.querySelectorAll('[data-pane-body] #project-request-select')].map(e => e.value)`;
+  await wait(`document.querySelectorAll('[data-pane-body] #project-request-select').length === 2`);
+  assert.deepEqual(await b.evaluate(values), ['request-1', 'request-1']);
+  await b.evaluate(`(() => { const e = document.querySelector('#pane-a #project-request-select'); e.value = 'request-2'; e.dispatchEvent(new Event('change', { bubbles: true })); })()`);
+  await wait(`${values}[0] === 'request-2'`);
+  await b.evaluate('window.MosaicPanes.refresh()');
+  await settled(b);
+  await wait(`document.querySelectorAll('[data-pane-body] #project-request-select').length === 2`);
+  assert.deepEqual(await b.evaluate(values), ['request-2', 'request-1']);
+});
+
+test('a pane keeps its request choice and PRD disclosure when a new conversation repaints the project', async t => {
+  const { b, wait } = await open(t);
+  await wait(`${title('b')}.includes("Forge")`);
+  const { stub, P } = await import('./helpers/projects-review-fixture.mjs');
+  await b.evaluate(stub.replace('const path=String(url),method', `if(url==='/api/orgs'||url==='/api/themes')return real(url,init);const path=String(url).replace(/^\\/api\\/orgs\\/(?:ddigital|forge)\\//,'/api/'),method`));
+  await b.evaluate('window.MosaicPanes.refresh()');
+  await wait(`document.querySelector('#pane-a-pick option[value="ddigital/projects/${P}"]')`);
+  // The same organization and project in both panes.
+  await b.evaluate(`location.hash = '#/orgs/ddigital/side-by-side?a=ddigital/projects/${P}/requirements&b=ddigital/projects/${P}/requirements'`);
+  await wait(`document.querySelectorAll('[data-pane-body] #project-request-select').length === 2 && document.querySelectorAll('[data-pane-body] .project-prd-toggle').length === 2`);
+  const state = `({ selected: [...document.querySelectorAll('[data-pane-body] #project-request-select')].map(e => e.value), expanded: [...document.querySelectorAll('[data-pane-body] [data-prd]')].map(e => e.classList.contains('expanded')) })`;
+  await b.evaluate(`(() => { const e = document.querySelector('#pane-a #project-request-select'); e.value = 'request-2'; e.dispatchEvent(new Event('change', { bubbles: true })); })()`);
+  await wait(`document.querySelector('#pane-a #project-request-select').value === 'request-2'`);
+  await b.evaluate(`document.querySelector('#pane-a .project-prd-toggle').click()`);
+  await wait(`document.querySelector('#pane-a [data-prd]')?.classList.contains('expanded')`);
+  // A new conversation changes the header's count, so each pane replaces its project content.
+  const before = await b.evaluate(`document.querySelector('#pane-a .project-header p')?.textContent || ''`);
+  await b.evaluate(`window.fixtureThreads.push({ ...window.fixtureThreads[0], id: '20000000-0000-4000-8000-000000000004', name: 'A new conversation' }); window.MosaicPanes.refresh()`);
+  await wait(`(() => { const t = document.querySelector('#pane-a .project-header p')?.textContent || ''; return t !== ${JSON.stringify(before)} && /4 conversations/.test(t) && /4 conversations/.test(document.querySelector('#pane-b .project-header p')?.textContent || ''); })()`);
+  await settled(b);
+  await wait(`document.querySelectorAll('[data-pane-body] #project-request-select').length === 2 && document.querySelectorAll('[data-pane-body] [data-prd]').length === 2`);
+  assert.deepEqual(await b.evaluate(state), { selected: ['request-2', 'request-1'], expanded: [true, false] });
+});
+
+test('a pane navigation that finishes late does not take focus from the other pane', async t => {
+  const { b, wait } = await open(t);
+  await wait(`document.querySelector('#pane-a [data-focus-key="agents-all"]') && document.querySelector('#pane-b-pick')?.options.length > 4`);
+  await b.evaluate(hold('/api/orgs/ddigital/bus/instances'));
+  await b.evaluate(`document.querySelector('#pane-a [data-focus-key="agents-all"]').click()`);
+  await wait('window.held.pending');
+  await b.evaluate(`document.querySelector('#pane-b-pick').focus(); window.held.release()`);
+  await wait(`${title('a')}.startsWith('Agents')`);
+  await settled(b);
+  assert.equal(await b.evaluate('document.activeElement.id'), 'pane-b-pick');
+  // Without a move elsewhere, the same navigation still lands on the new page's heading.
+  await pick(b, 'a', 'ddigital/organization');
+  await wait(`document.querySelector('#pane-a [data-focus-key="agents-all"]')`);
+  await b.evaluate(`document.querySelector('#pane-a [data-focus-key="agents-all"]').click()`);
+  await wait(`${title('a')}.startsWith('Agents') && document.activeElement?.tagName === 'H1' && document.querySelector('#pane-a').contains(document.activeElement)`);
+});
+
+// A1's "Available in a project" chooser, with an Agents pane per organization: each pane's choice
+// redraws its own table and survives a refresh, keyed by that pane's organization.
+test('each Agents pane keeps its own project choice for its organization', async t => {
+  const { b, wait } = await open(t, { hash: '#/orgs/ddigital/side-by-side?a=ddigital/agents&b=forge/agents' });
+  const a = (name, level = 'org', definition = name) => ({ name, level, definition, model: null, scope: { kind: 'org' }, overrides: [], narrowed: [] });
+  const set = agents => ({ state: 'ok', agents, excluded: [] });
+  const levels = { root: { state: 'ok', assistant: null, agents: [] }, orgs: [
+    { id: 'ddigital', state: 'ok', base: set([a('chief')]), defined: { 'spring-launch': [{ name: 'social-scheduler', form: 'define' }] },
+      projects: { 'spring-launch': set([a('chief'), a('social-scheduler', 'project', 'coder')]), 'brand-refresh': set([a('chief')]) } },
+    { id: 'forge', state: 'ok', base: set([a('chief')]), defined: { 'api-gateway': [{ name: 'load-tester', form: 'define' }] },
+      projects: { 'api-gateway': set([a('chief'), a('load-tester', 'project', 'coder')]), ops: set([a('chief')]) } },
+  ] };
+  await b.evaluate(`(() => { const real = window.fetch; window.fetch = (url, init) => String(url).endsWith('/api/agents/levels') ? Promise.resolve(new Response(${JSON.stringify(JSON.stringify(levels))}, { headers: { 'content-type': 'application/json' } })) : real(url, init); })()`);
+  await b.evaluate('window.MosaicPanes.refresh()');
+  const select = key => `document.querySelector('#pane-${key} [data-agents-project]')`;
+  const rows = key => `[...document.querySelectorAll('#pane-${key} [data-agents-available] tr[data-agent]')].map(r => r.dataset.agent)`;
+  await wait(`${select('a')} && ${select('b')} && ${rows('a')}.includes('social-scheduler') && ${rows('b')}.includes('load-tester')`);
+  await b.evaluate(`(() => { const s = ${select('b')}; s.value = 'ops'; s.dispatchEvent(new Event('change', { bubbles: true })); })()`);
+  await wait(`!${rows('b')}.includes('load-tester')`);
+  assert.equal(await b.evaluate(`${rows('a')}.includes('social-scheduler')`), true);
+  assert.equal(await b.evaluate(`${rows('a')}.includes('load-tester')`), false);
+  await b.evaluate('window.MosaicPanes.refresh()');
+  await settled(b);
+  await wait(`${select('a')} && ${select('b')}`);
+  assert.deepEqual(await b.evaluate(`[${select('a')}.value, ${select('b')}.value]`), ['spring-launch', 'ops']);
+  assert.equal(await b.evaluate(`!${rows('b')}.includes('load-tester') && ${rows('a')}.includes('social-scheduler')`), true);
+});
@@ -0,0 +1,244 @@
+// Phase P2 (#1873): System types on the organization dashboard (sample 03) and on a project's information
+// page. The Console, its per-organization routes and the pages are real; only the two bus transports are
+// the fake in helpers/system-types-fake.mjs, which reads the installed modules from packages/plugins. The
+// server-side admission checks and the real organization writer are in system-types-http.test.mjs.
+// MOSAIC_UX_SHOTS=<dir> also writes light and dark shots at 1440x900 and 390x844.
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdirSync } from 'node:fs';
+import { join } from 'node:path';
+import { startServer } from '../src/serve.mjs';
+import { createDevOwner } from '../src/dev-owner.mjs';
+import { browser } from './browser.mjs';
+import { close } from './fixture.mjs';
+import { systemTypesFake } from './helpers/system-types-fake.mjs';
+
+const P = '10000000-0000-4000-8000-0000000000b1';
+const RECEIPT = /Receipt ([0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})\./;
+const waitFor = b => expression => b.evaluate(`(async()=>{for(let i=0;i<300;i++){if(${expression})return true;await new Promise(r=>setTimeout(r,30))}throw Error(${JSON.stringify(expression)}+' | '+(document.querySelector('main')?.innerText||'').slice(0,1500))})()`);
+
+// One running organization with one project. `send` is the owner's signed-in send mode; without it the
+// Console only reads and the route gets no writer.
+function organizations(st, { send = true } = {}) {
+  const business = { business: { id: 'acme', human: 'jason', arbiters: [], projects: [P], vars: {}, instances: [], appearance: { theme: null } } };
+  return {
+    list: async () => [{ id: 'acme', label: 'Acme', theme: null, busHealthy: true }],
+    resolve: async id => id !== 'acme' ? null : ({
+      busHealthy: true, requestRead: st.requestRead, systemTypesWrite: send ? st.systemTypesWrite : null, ...(send ? { send: async () => ({}) } : {}),
+      reads: { business: async () => business, settings: async () => ({}), queue: async () => ({ rows: [] }), busStatus: async () => ({}) },
+      bus: { instances: async () => ({ business: 'acme', revision: 'a'.repeat(64), launch: true, noHire: [], retired: [], definitions: {}, instances: {} }),
+        messages: async () => ({ messages: [], unread: 0 }), agents: async () => [], 'thread.claims': async () => [], inbox: async () => [], tasks: async () => [] },
+      chat: { projects: async () => [{ id: P, name: 'Work', repo: null }], threads: async () => [] },
+    }),
+  };
+}
+
+async function page(t, st, { send = true, width = 1440, height = 900 } = {}) {
+  const server = await startServer({ port: 0, sso: createDevOwner(), ...(send ? { send: async () => ({}) } : {}), organizations: organizations(st, { send }), log: () => {} });
+  t.after(() => close(server));
+  const b = await browser({ machine: false }); t.after(() => b.close());
+  const errors = [];
+  b.on('Runtime.exceptionThrown', p => errors.push(p.exceptionDetails?.exception?.description ?? p.exceptionDetails?.text ?? 'exception'));
+  await b.viewport(width, height);
+  const base = `http://127.0.0.1:${server.address().port}/`;
+  return { b, base, wait: waitFor(b), errors };
+}
+const dashboard = async ({ b, base, wait }) => {
+  await b.navigate(`${base}#/orgs/acme/organization`);
+  await wait('document.querySelector("[data-org-dashboard] [data-system-types]") && !/Reading/.test(document.querySelector("[data-system-types]").textContent)');
+};
+const settings = async ({ b, base, wait }) => {
+  await b.navigate(`${base}#/orgs/acme/projects/${P}/settings`);
+  await wait('document.querySelector("[data-project-system-types]") && !/Reading system types/.test(document.querySelector("[data-project-system-types]").textContent)');
+};
+const text = (b, selector) => b.evaluate(`(document.querySelector(${JSON.stringify(selector)})?.innerText ?? '').replace(/\\s+/g, ' ').trim()`);
+const chips = b => b.evaluate(`[...document.querySelectorAll('[data-system-type-chips] .ws-chip')].map(c => c.textContent)`);
+const click = (b, selector) => b.evaluate(`(document.querySelector(${JSON.stringify(selector)}).click(), true)`);
+
+test('the dashboard lists the installed modules from the plug-in data and the owner switches one with a receipt', { timeout: 60000 }, async t => {
+  const st = await systemTypesFake({ enabled: ['coding'], projects: { [P]: [] } });
+  const p = await page(t, st); const { b, wait } = p;
+  await dashboard(p);
+  // Every row is a module the plug-ins declare, in their order, with their label and description.
+  const rows = await b.evaluate(`[...document.querySelectorAll('[data-system-types] li')].map(li => [li.dataset.systemType, li.querySelector('.t b').textContent, li.querySelector('.t .d').textContent, li.querySelector('.ws-dot').textContent.replace(/[●–]/, '')])`);
+  assert.deepEqual(rows, st.installed.map(m => [m.id, m.label, m.description, m.id === 'coding' ? 'enabled' : 'off']));
+  assert.ok(st.installed.length >= 2, 'the tree installs more than one system type module');
+  assert.deepEqual(await chips(b), ['Coding']);
+  assert.match(await text(b, '[data-system-type-chips]'), /Each project picks from these; none is required\.$/);
+  assert.match(await text(b, '[data-org-setting="System types"]'), new RegExp(`1 of ${st.installed.length} installed enabled`));
+  // The Settings row's Open moves focus to the section heading.
+  await click(b, '[data-org-setting="System types"] [data-system-types-open]');
+  assert.equal(await b.evaluate('document.activeElement?.dataset.systemTypesHeading'), '');
+
+  // Enable Marketing from the keyboard; the receipt is the organization writer's transaction.
+  await b.evaluate(`document.querySelector('[data-system-type-toggle="marketing"]').focus(), true`);
+  assert.equal(await b.evaluate(`document.activeElement.getAttribute('aria-label')`), 'Enable Marketing');
+  await b.key('Enter');
+  await wait(`/Receipt/.test(document.querySelector('[data-system-types-status]')?.textContent)`);
+  assert.match(await text(b, '[data-system-types-status]'), new RegExp(`^Marketing enabled\\. ${RECEIPT.source}$`));
+  assert.deepEqual(st.state.enabled, ['coding', 'marketing']);
+  assert.deepEqual(await chips(b), ['Coding', 'Marketing']);
+  assert.match(await text(b, '[data-org-setting="System types"]'), new RegExp(`2 of ${st.installed.length} installed enabled`));
+  // Focus stays on the switch it pressed, which now says Disable.
+  assert.deepEqual(await b.evaluate(`[document.activeElement.dataset.focusKey, document.activeElement.getAttribute('aria-label')]`), ['st:marketing', 'Disable Marketing']);
+
+  // Disable Coding; another write changed the organization file meanwhile, so the first try is refused.
+  st.state.n++;
+  await click(b, '[data-system-type-toggle="coding"]');
+  await wait(`/changed after this page read it/.test(document.querySelector('[data-system-types-status]')?.textContent)`);
+  assert.deepEqual(st.state.enabled, ['coding', 'marketing']);
+  await click(b, '[data-system-type-toggle="coding"]');
+  await wait(`/Coding disabled/.test(document.querySelector('[data-system-types-status]')?.textContent)`);
+  assert.match(await text(b, '[data-system-types-status]'), RECEIPT);
+  assert.deepEqual(st.state.enabled, ['marketing']);
+  assert.equal(await b.evaluate(`document.querySelector('[data-system-type="coding"] .ws-dot').textContent.replace(/[●–]/, '')`), 'off');
+  assert.deepEqual(p.errors, []);
+});
+
+test('without the owner proof the switch is refused, and a read-only Console offers none', { timeout: 60000 }, async t => {
+  // The writer's owner fence refuses: the page says so and nothing changes.
+  const fenced = await systemTypesFake({ enabled: ['coding'], projects: { [P]: [] }, owner: false });
+  const p = await page(t, fenced); const { b, wait } = p;
+  await dashboard(p);
+  await click(b, '[data-system-type-toggle="marketing"]');
+  await wait(`/owner can change/.test(document.querySelector('[data-system-types-status]')?.textContent)`);
+  assert.equal(await text(b, '[data-system-types-status]'), "Only the organization's owner can change system types.");
+  assert.deepEqual(fenced.state.enabled, ['coding']);
+  assert.doesNotMatch(await text(b, '[data-system-types]'), /Receipt/);
+
+  // A Console without send mode reads the list and shows no switch; no write reaches the transport.
+  const readOnly = await systemTypesFake({ enabled: ['coding'], projects: { [P]: ['coding'] } });
+  const q = await page(t, readOnly, { send: false });
+  await dashboard(q);
+  assert.equal(await q.b.evaluate(`document.querySelectorAll('[data-system-types] li').length`), readOnly.installed.length);
+  assert.equal(await q.b.evaluate(`document.querySelectorAll('[data-system-type-toggle]').length`), 0);
+  assert.match(await text(q.b, '[data-system-types]'), /This Console only reads\. Changing system types needs signed-in send mode\./);
+  // The project page shows the selection read only too.
+  await settings(q);
+  assert.equal(await q.b.evaluate(`[...document.querySelectorAll('[data-project-system-types] input')].every(i => i.disabled)`), true);
+  assert.equal(await q.b.evaluate(`document.querySelector('[data-project-system-types] button[type=submit]')`), null);
+  assert.deepEqual(readOnly.state.writes, []);
+});
+
+test('a project selects only enabled modules and a disabled selection shows as inactive', { timeout: 60000 }, async t => {
+  // Montage was selected, then disabled in the organization.
+  const st = await systemTypesFake({ enabled: ['coding', 'marketing'], projects: { [P]: ['montage'] } });
+  const p = await page(t, st); const { b, wait } = p;
+  await settings(p);
+  const label = id => st.installed.find(m => m.id === id).label;
+  assert.deepEqual(await b.evaluate(`[...document.querySelectorAll('[data-project-system-types] input[name=system-type]')].map(i => [i.value, i.checked, i.closest('label').querySelector('strong').textContent])`),
+    [['coding', false, label('coding')], ['marketing', false, label('marketing')]]);
+  assert.deepEqual(await b.evaluate(`[...document.querySelectorAll('[data-inactive-type]')].map(li => [li.dataset.inactiveType, li.innerText.replace(/\\s+/g, ' ').trim()])`), [['montage', `${label('montage')} inactive`]]);
+  assert.match(await text(b, '[data-project-system-types-inactive]'), /Saving keeps only enabled types/);
+
+  // Pick Marketing and save: the inactive one goes, the saved selection is the bus's answer.
+  await b.evaluate(`document.querySelector('[data-project-system-types] input[value=marketing]').click(), true`);
+  await click(b, '[data-project-system-types] button[type=submit]');
+  await wait(`/Saved/.test(document.querySelector('[data-project-system-types-status]')?.textContent)`);
+  assert.equal(await text(b, '[data-project-system-types-status]'), `Saved. Selected: ${label('marketing')}.`);
+  assert.equal(await b.evaluate(`document.activeElement?.hasAttribute('data-project-system-types-status')`), true);
+  assert.deepEqual(st.state.projects[P], ['marketing']);
+  assert.equal(await b.evaluate(`document.querySelector('[data-inactive-type]')`), null);
+
+  // The organization disables Coding after the page read it; saving it is refused and the list is read again.
+  await b.evaluate(`document.querySelector('[data-project-system-types] input[value=coding]').click(), true`);
+  st.state.enabled = ['marketing'];
+  await click(b, '[data-project-system-types] button[type=submit]');
+  await wait(`/not enabled in the organization/.test(document.querySelector('[data-project-system-types-status]')?.textContent)`);
+  assert.deepEqual(st.state.projects[P], ['marketing']);
+  assert.deepEqual(await b.evaluate(`[...document.querySelectorAll('[data-project-system-types] input[name=system-type]')].map(i => i.value)`), ['marketing']);
+
+  // The owner disables Marketing on the dashboard; back on the project it stays selected, shown inactive.
+  await dashboard(p);
+  await click(b, '[data-system-type-toggle="marketing"]');
+  await wait(`/Marketing disabled/.test(document.querySelector('[data-system-types-status]')?.textContent)`);
+  assert.deepEqual(st.state.enabled, []);
+  await settings(p);
+  assert.match(await text(b, '[data-project-system-types]'), /The organization has no system types enabled\./);
+  assert.deepEqual(await b.evaluate(`[...document.querySelectorAll('[data-inactive-type]')].map(li => li.dataset.inactiveType)`), ['marketing']);
+  assert.equal(await b.evaluate(`document.querySelectorAll('[data-project-system-types] input').length`), 0);
+  // With nothing enabled the owner can still clear the inactive selection, without enabling a type first.
+  assert.equal(await text(b, '[data-project-system-types] button[type=submit]'), 'Clear the inactive types');
+  await click(b, '[data-project-system-types] button[type=submit]');
+  await wait(`/Saved/.test(document.querySelector('[data-project-system-types-status]')?.textContent)`);
+  assert.equal(await text(b, '[data-project-system-types-status]'), 'Saved. No system types selected.');
+  assert.deepEqual(st.state.projects[P], []);
+  assert.deepEqual(st.state.enabled, []);
+  assert.equal(await b.evaluate(`document.querySelector('[data-inactive-type]')`), null);
+  assert.equal(await b.evaluate(`document.querySelector('[data-project-system-types] button[type=submit]')`), null);
+  assert.deepEqual(p.errors, []);
+
+  // A read-only Console shows the same inactive selection and offers no clear button.
+  const readOnly = await systemTypesFake({ enabled: [], projects: { [P]: ['coding'] } });
+  const q = await page(t, readOnly, { send: false });
+  await settings(q);
+  assert.deepEqual(await q.b.evaluate(`[...document.querySelectorAll('[data-inactive-type]')].map(li => li.dataset.inactiveType)`), ['coding']);
+  assert.equal(await q.b.evaluate(`document.querySelector('[data-project-system-types] button[type=submit]')`), null);
+  assert.deepEqual(readOnly.state.writes, []);
+});
+
+test('the dashboard section and the project page fit a phone screen in light and dark', { timeout: 90000 }, async t => {
+  const st = await systemTypesFake({ enabled: ['coding', 'marketing'], projects: { [P]: ['coding', 'montage'] } });
+  const shots = process.env.MOSAIC_UX_SHOTS;
+  if (shots) mkdirSync(shots, { recursive: true });
+  for (const [width, height] of [[1440, 900], [390, 844]]) {
+    const p = await page(t, st, { width, height }); const { b } = p;
+    for (const mode of ['light', 'dark']) {
+      await b.call('Emulation.setEmulatedMedia', { features: [{ name: 'prefers-color-scheme', value: mode }] });
+      await dashboard(p);
+      // The default appearance is Harbor in the dark whatever the OS says; the header switch picks the mode.
+      if (await b.evaluate(`document.getElementById('theme-switch').getAttribute('aria-checked')`) !== String(mode === 'dark')) {
+        await b.evaluate(`document.getElementById('theme-switch').click(), true`);
+        await p.wait(`document.getElementById('theme-switch').getAttribute('aria-checked') === '${mode === 'dark'}'`);
+      }
+      await b.evaluate(`document.querySelector('[data-system-types-heading]').scrollIntoView({ block: 'start' }), true`);
+      assert.equal(await b.evaluate('document.documentElement.scrollWidth <= document.documentElement.clientWidth'), true, `dashboard ${width} ${mode}`);
+      assert.equal(await b.evaluate(`[...document.querySelectorAll('[data-system-types] li')].every(li => li.scrollWidth <= li.clientWidth)`), true, `dashboard rows ${width} ${mode}`);
+      if (shots) await b.screenshot(join(shots, `p2-dashboard-types-${width}-${mode}.png`));
+      await settings(p);
+      await b.evaluate(`document.querySelector('[data-project-system-types]').scrollIntoView({ block: 'start' }), true`);
+      // At 1440 a project page taller than the window already overflows by its header's primary action
+      // (projects.css, before P2), so the wide check is the section's own box; the phone check is the page.
+      if (width === 390) assert.equal(await b.evaluate('document.documentElement.scrollWidth <= document.documentElement.clientWidth'), true, `project ${width} ${mode}`);
+      assert.equal(await b.evaluate(`(s => s.scrollWidth <= s.clientWidth && s.getBoundingClientRect().right <= document.documentElement.clientWidth)(document.querySelector('[data-project-system-types]'))`), true, `project section ${width} ${mode}`);
+      assert.equal(await b.evaluate(`[...document.querySelectorAll('[data-project-system-types] .project-types-option')].every(o => o.getBoundingClientRect().height >= 44)`), true, `targets ${width} ${mode}`);
+      if (shots) await b.screenshot(join(shots, `p2-project-types-${width}-${mode}.png`));
+    }
+    assert.deepEqual(p.errors, []);
+  }
+});
+
+// U5's Side by side draws an organization dashboard into a pane. Each pane reads its own organization's
+// system types; a pane only shows them (the switch stays in the organization's full view, as the bus
+// restart does), and its Settings row opens the section in the same pane.
+test('a side-by-side pane shows its own organization\'s system types and offers no switch', { timeout: 60000 }, async t => {
+  const acme = await systemTypesFake({ enabled: ['coding'], projects: { [P]: [] } });
+  const beta = await systemTypesFake({ enabled: ['marketing'], projects: {} });
+  const one = organizations(acme);
+  const server = await startServer({ port: 0, sso: createDevOwner(), send: async () => ({}), log: () => {}, organizations: {
+    list: async () => [{ id: 'acme', label: 'Acme', theme: null, busHealthy: true }, { id: 'beta', label: 'Beta', theme: null, busHealthy: true }],
+    resolve: async id => id === 'acme' ? one.resolve('acme') : id === 'beta' ? { ...(await one.resolve('acme')), requestRead: beta.requestRead, systemTypesWrite: beta.systemTypesWrite,
+      chat: { projects: async () => [], threads: async () => [] } } : null,
+  } });
+  t.after(() => close(server));
+  const b = await browser({ machine: false }); t.after(() => b.close());
+  const errors = [];
+  b.on('Runtime.exceptionThrown', p => errors.push(p.exceptionDetails?.exception?.description ?? p.exceptionDetails?.text ?? 'exception'));
+  await b.viewport(1440, 900);
+  const wait = waitFor(b);
+  await b.navigate(`http://127.0.0.1:${server.address().port}/#/orgs/acme/side-by-side?a=acme/organization&b=beta/organization`);
+  const ready = key => `document.querySelector('#pane-${key} [data-system-types]') && !/Reading/.test(document.querySelector('#pane-${key} [data-system-types]').textContent)`;
+  await wait(`${ready('a')} && ${ready('b')}`);
+  const paneChips = key => b.evaluate(`[...document.querySelectorAll('#pane-${key} [data-system-type-chips] .ws-chip')].map(c => c.textContent)`);
+  assert.deepEqual(await paneChips('a'), ['Coding']);
+  assert.deepEqual(await paneChips('b'), ['Marketing']);
+  assert.equal(await b.evaluate(`document.querySelectorAll('.panes [data-system-type-toggle]').length`), 0);
+  for (const key of ['a', 'b'])
+    assert.match(await text(b, `#pane-${key} [data-system-types]`), /Change system types from this organization's full view\./);
+  const ids = await b.evaluate(`[...document.querySelectorAll('[data-system-types-heading]')].map(h => h.id)`);
+  assert.equal(ids.length, 2); assert.equal(new Set(ids).size, 2);
+  await click(b, '#pane-b [data-org-setting="System types"] [data-system-types-open]');
+  assert.equal(await b.evaluate(`document.activeElement === document.querySelector('#pane-b [data-system-types-heading]')`), true);
+  assert.deepEqual([acme.state.writes.includes('plugins.set'), beta.state.writes.includes('plugins.set')], [false, false]);
+  assert.deepEqual(errors, []);
+});
@@ -0,0 +1,235 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { mkdtempSync, mkdirSync, readFileSync, rmSync } from 'node:fs';
+import { request } from 'node:http';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { businessDoc, rolesCopy, systemFor, writeJson } from '../../organization/tests/helpers.mjs';
+import { loadBusiness } from '../../organization/src/organization-config.mjs';
+import { resolveInstance } from '../../organization/src/resolve.mjs';
+import { busOrganization } from '../../bus/src/organization-context.mjs';
+import { startBroker } from '../../bus/src/runtime.mjs';
+import { serve } from '../../bus/src/server.mjs';
+import { Client } from '../../bus/src/client.mjs';
+import { installedSystemTypes } from '../../plugins/src/system-types.mjs';
+import { startServer } from '../src/serve.mjs';
+import { close } from './fixture.mjs';
+
+// Phase P2 (#1873): the owner's System types routes on a selected organization, end to end. An
+// ephemeral organization with the real runtime writer (plugins.set, the system types owner fence,
+// changes.jsonl) and the broker's console socket for the read; the SSO session is a fixture
+// authority. `writer` picks the cap the write transport binds: the owner's human cap, or the tester.
+async function fixture(t, { writer = 'owner', send = true, afterRead = null, beforeWrite = null } = {}) {
+  // Cleanups run last-made first, registered as soon as each resource exists.
+  const undo = []; t.after(async () => { for (const step of undo.reverse()) await step(); });
+  const root = mkdtempSync(join(tmpdir(), 'st-'));
+  const rolesDir = rolesCopy(root), system = systemFor(root);
+  const doc = businessDoc(root, 'demo');
+  doc.plugins = { ...(doc.plugins ?? {}), 'system-type': ['coding'], harness: ['pi'] };
+  doc.vars = { ...doc.vars, 'bus.tester': true };
+  const file = writeJson(join(root, 'businesses/demo.json'), doc);
+  mkdirSync(join(root, 'data'), { mode: 0o700 });
+  const business = loadBusiness('demo', { dir: root, rolesDir });
+  const resolved = Object.fromEntries(Object.keys(business.roles).map(instance => [instance, resolveInstance({ system, business, instance })]));
+  undo.push(() => rmSync(root, { recursive: true, force: true }));
+  const runtime = await startBroker({ dataRoot: join(root, 'data'), businesses: { demo: busOrganization(business, resolved) }, organization: { dir: root, rolesDir, system } });
+  undo.push(() => runtime.close());
+  const path = join(root, 'b.sock');
+  const socketServer = await serve({ broker: runtime.broker, path, peerReader: { read: async () => ({}), close: () => {} },
+    authenticateConsole: proof => runtime.broker.bindConsole({ business: 'demo', human: 'jason', subject: proof.subject }) });
+  undo.push(() => socketServer.close());
+  const owner = runtime.broker.bindHuman({ business: 'demo', human: 'jason', via: 'cli', outsideAgent: true });
+  const role = Object.keys(business.roles)[0];
+  const cap = writer === 'tester' ? runtime.broker.bindTester({ business: 'demo' })
+    : writer === 'agent' ? runtime.broker.bindLaunch({ business: 'demo', role, run: 'agent-run', harness: 'pi' }) : owner;
+  const calls = [];
+  // afterRead and beforeWrite let a test act between the route's read and its write.
+  const requestRead = async (verb, args, ctx) => { calls.push(['read', verb]); const r = await new Client({ path, console: { subject: ctx.subject } }).call(verb, args); await afterRead?.(); return r; };
+  const systemTypesWrite = async (verb, args) => { await beforeWrite?.(verb); calls.push(['write', verb]); return runtime.broker.request(cap, { verb, args }); };
+  const session = { provider: 'fixture', iss: 'https://issuer.example', sub: 'owner', name: 'jason' };
+  let active = true;
+  const sso = { publicOrigin: '', publicHost: '', formTargets: () => [], session: () => active ? session : null, handle: () => {}, health: () => ({}) };
+  const organizations = {
+    list: async () => [{ id: 'demo', label: 'Demo', busHealthy: true }],
+    resolve: async id => id !== 'demo' ? null : { busHealthy: true, send: send ? async () => ({}) : null, requestRead, systemTypesWrite: send ? systemTypesWrite : null,
+      reads: { business: async () => ({ business: { id: 'demo' } }) }, bus: {}, chat: { projects: async () => [], threads: async () => [] } },
+  };
+  const web = await startServer({ port: 0, board: 'http://127.0.0.1:9', sso, send: async () => ({}), organizations, log: () => {} });
+  const base = `http://127.0.0.1:${web.address().port}`;
+  sso.publicOrigin = base; sso.publicHost = new URL(base).host;
+  undo.push(() => close(web));
+  const project = runtime.broker.request(owner, { verb: 'project.create', args: { name: 'example' } }).id;
+  const onDisk = () => JSON.parse(readFileSync(file)).plugins['system-type'];
+  const ownerRequest = (verb, args) => runtime.broker.request(owner, { verb, args });
+  return { base, file, project, calls, onDisk, ownerRequest, signOut: () => { active = false; } };
+}
+
+function call(f, path, method = 'GET', body, headers = {}) {
+  return new Promise((resolve, reject) => {
+    const data = body === undefined ? undefined : typeof body === 'string' ? body : JSON.stringify(body);
+    const req = request(f.base + path, { method, headers: { ...(data !== undefined ? { origin: f.base, 'sec-fetch-site': 'same-origin', 'content-type': 'application/json', 'content-length': Buffer.byteLength(data) } : {}), ...headers } }, res => {
+      let text = ''; res.on('data', chunk => { text += chunk; }); res.on('end', () => resolve([res.statusCode, JSON.parse(text)]));
+    });
+    req.on('error', reject); req.setTimeout(10000, () => req.destroy(new Error('fixture request timed out'))); req.end(data);
+  });
+}
+const ORG = '/api/orgs/demo/system-types';
+
+test('the owner reads the installed modules and enables one with the revision, getting a receipt', async t => {
+  const f = await fixture(t);
+  const [status, before] = await call(f, ORG);
+  assert.equal(status, 200, JSON.stringify(before));
+  // Labels and descriptions are the modules' own, never a list in the WebUI.
+  const modules = (await installedSystemTypes()).map(({ id, label, description }) => ({ id, label, description }));
+  assert.deepEqual(before.installed, modules);
+  assert.deepEqual(before.enabled, ['coding']);
+  assert.equal(before.project, null); assert.equal(before.writable, true); assert.match(before.revision, /^[a-f0-9]{64}$/);
+  const [saved, receipt] = await call(f, ORG, 'POST', { revision: before.revision, enabled: ['coding', 'montage'] });
+  assert.equal(saved, 200, JSON.stringify(receipt));
+  assert.deepEqual(receipt.enabled, ['coding', 'montage']);
+  assert.match(receipt.transaction, /^[0-9a-f-]{36}$/); assert.notEqual(receipt.revision, before.revision);
+  assert.deepEqual(f.onDisk(), ['coding', 'montage']);
+  const [, after] = await call(f, ORG);
+  assert.deepEqual(after.enabled, ['coding', 'montage']); assert.equal(after.revision, receipt.revision);
+  // The revision is the proof: the old one is refused and nothing is written.
+  const [stale, conflict] = await call(f, ORG, 'POST', { revision: before.revision, enabled: [] });
+  assert.deepEqual([stale, conflict.error], [409, 'revision-conflict']);
+  assert.deepEqual(f.onDisk(), ['coding', 'montage']);
+});
+
+test('the admission checks refuse before any write', async t => {
+  const f = await fixture(t);
+  const [, { revision }] = await call(f, ORG);
+  const good = { revision, enabled: [] };
+  for (const [label, body, headers, expected] of [
+    ['unknown module', { revision, enabled: ['nope'] }, {}, [400, 'system-type-unknown']],
+    ['duplicate', { revision, enabled: ['coding', 'coding'] }, {}, [400, 'invalid-request']],
+    ['extra field', { ...good, actor: 'jason' }, {}, [400, 'invalid-request']],
+    ['business field', { ...good, business: 'other' }, {}, [400, 'invalid-request']],
+    ['no revision', { enabled: [] }, {}, [400, 'invalid-request']],
+    ['bad revision', { revision: 'x', enabled: [] }, {}, [400, 'invalid-request']],
+    ['not JSON', '{', {}, [400, 'invalid-request']],
+    ['too large', JSON.stringify({ revision, enabled: [], pad: 'x'.repeat(5000) }), {}, [413, 'invalid-request']],
+    ['form post', good, { 'content-type': 'text/plain' }, [400, 'invalid-request']],
+    // The Console's own origin check answers a foreign Origin first; the route's own check answers Sec-Fetch-Site.
+    ['cross origin', good, { origin: 'https://other.example' }, [403, 'cross-origin request refused']],
+    ['cross site', good, { 'sec-fetch-site': 'cross-site' }, [403, 'cross-origin']],
+  ]) {
+    const writes = f.calls.filter(c => c[0] === 'write' && c[1] === 'plugins.set').length;
+    const [status, result] = await call(f, ORG, 'POST', body, headers);
+    assert.deepEqual([status, result.error], expected, label);
+    assert.equal(f.calls.filter(c => c[0] === 'write' && c[1] === 'plugins.set').length, writes, label);
+    assert.deepEqual(f.onDisk(), ['coding'], label);
+  }
+  const [method] = await call(f, ORG, 'PUT');
+  assert.equal(method, 405);
+  const [cross, crossBody] = await call(f, ORG, 'GET', undefined, { origin: 'https://other.example' });
+  assert.equal(cross, 403); assert.match(crossBody.error, /^cross-origin/);
+  const [badProject, badProjectBody] = await call(f, `${ORG}/projects/${encodeURIComponent('../x')}`);
+  assert.deepEqual([badProject, badProjectBody.error], [404, 'project-not-found']);
+  f.signOut();
+  const [signedOut, signedOutBody] = await call(f, ORG, 'POST', good);
+  assert.deepEqual([signedOut, signedOutBody.error], [401, 'sign-in-required']);
+  assert.deepEqual(f.onDisk(), ['coding']);
+});
+
+test('a sign-out while the read runs dispatches no write on either route', async t => {
+  let signOutOnRead = false;
+  const f = await fixture(t, { afterRead: () => { if (signOutOnRead) f.signOut(); } });
+  const [, { revision }] = await call(f, ORG);
+  signOutOnRead = true;
+  const writes = () => f.calls.filter(c => c[0] === 'write' && c[1] !== 'plugins').length;
+  for (const [path, body] of [[ORG, { revision, enabled: [] }], [`${ORG}/projects/${f.project}`, { systemTypes: ['coding'] }]]) {
+    const [status, result] = await call(f, path, 'POST', body);
+    assert.deepEqual([status, result.error], [401, 'sign-in-required'], path);
+  }
+  assert.equal(writes(), 0);
+  assert.deepEqual(f.onDisk(), ['coding']);
+});
+
+test('the enabled set and its revision come from one read, so a change in between is not undone', async t => {
+  let raced = false;
+  const f = await fixture(t, { beforeWrite: async verb => {
+    // Another owner action enables Marketing after the route's Console read and before its plugins read.
+    if (verb !== 'plugins' || raced) return;
+    raced = true;
+    const { revision } = await f.ownerRequest('plugins', {});
+    await f.ownerRequest('plugins.set', { revision, plugins: { 'system-type': ['coding', 'marketing'] } });
+  } });
+  const [, view] = await call(f, ORG);
+  assert.equal(raced, true);
+  assert.deepEqual(view.enabled, ['coding', 'marketing']);
+  const [saved, receipt] = await call(f, ORG, 'POST', { revision: view.revision, enabled: view.enabled.filter(x => x !== 'coding') });
+  assert.equal(saved, 200, JSON.stringify(receipt));
+  assert.deepEqual(f.onDisk(), ['marketing']);
+});
+
+test('without the owner human proof the enable switch is refused', async t => {
+  // A Console without --send has no write transport: the read works, the write is read-only.
+  const readOnly = await fixture(t, { send: false });
+  const [status, view] = await call(readOnly, ORG);
+  assert.equal(status, 200); assert.equal(view.writable, false); assert.equal(view.revision, undefined);
+  const [refused, body] = await call(readOnly, ORG, 'POST', { revision: 'a'.repeat(64), enabled: [] });
+  assert.deepEqual([refused, body.error], [403, 'read-only']);
+  assert.deepEqual(readOnly.onDisk(), ['coding']);
+  // A write transport bound as the tester or as an agent, not the owner's human cap, is refused by the
+  // broker, and the receipt-bearing path never runs.
+  for (const writer of ['tester', 'agent']) {
+    const f = await fixture(t, { writer });
+    const [fenced, fence] = await call(f, ORG, 'POST', { revision: 'b'.repeat(64), enabled: [] });
+    assert.deepEqual([fenced, fence.error], [403, 'human-required'], writer);
+    assert.deepEqual(f.onDisk(), ['coding'], writer);
+  }
+});
+
+test('a project selects only enabled modules and a disabled selection reads as inactive', async t => {
+  const f = await fixture(t);
+  const path = `${ORG}/projects/${f.project}`;
+  const [status, empty] = await call(f, path);
+  assert.equal(status, 200, JSON.stringify(empty));
+  assert.deepEqual(empty.project, { project: f.project, selected: [], active: [], inactive: [] });
+  assert.equal(empty.revision, undefined);
+  const [notEnabled, notEnabledBody] = await call(f, path, 'POST', { systemTypes: ['montage'] });
+  assert.deepEqual([notEnabled, notEnabledBody.error], [409, 'system-type-not-enabled']);
+  const [unknown, unknownBody] = await call(f, path, 'POST', { systemTypes: ['nope'] });
+  assert.deepEqual([unknown, unknownBody.error], [400, 'system-type-unknown']);
+  const [saved, selection] = await call(f, path, 'POST', { systemTypes: ['coding'] });
+  assert.equal(saved, 200, JSON.stringify(selection));
+  assert.deepEqual(selection, { project: f.project, selected: ['coding'], active: ['coding'], inactive: [] });
+  // The owner disables coding for the organization; the project keeps its selection, now inactive.
+  const [, { revision }] = await call(f, ORG);
+  assert.equal((await call(f, ORG, 'POST', { revision, enabled: [] }))[0], 200);
+  const [, after] = await call(f, path);
+  assert.deepEqual(after.enabled, []);
+  assert.deepEqual(after.project, { project: f.project, selected: ['coding'], active: [], inactive: ['coding'] });
+  const [missing, missingBody] = await call(f, `${ORG}/projects/no-such-project`);
+  assert.deepEqual([missing, missingBody.error], [404, 'project-not-found']);
+  const [missingWrite, missingWriteBody] = await call(f, `${ORG}/projects/no-such-project`, 'POST', { systemTypes: [] });
+  assert.deepEqual([missingWrite, missingWriteBody.error], [404, 'project-not-found']);
+});
+
+test('the tester listener and a Console without SSO never reach the routes or the files', async t => {
+  const { createDevOwner } = await import('../src/dev-owner.mjs');
+  let reached = 0;
+  const hit = async () => { reached++; return {}; };
+  const organizations = { list: async () => [{ id: 'demo', label: 'Demo', busHealthy: true }],
+    resolve: async () => ({ busHealthy: true, send: hit, requestRead: hit, systemTypesWrite: hit, reads: { business: async () => ({ business: { id: 'demo' } }) }, bus: {}, chat: { projects: async () => [], threads: async () => [] } }) };
+  const root = mkdtempSync(join(tmpdir(), 'stt-')), socket = join(root, 't.sock');
+  const tester = await startServer({ tester: true, testerSocket: socket, board: 'http://127.0.0.1:9', organizations, log: () => {} });
+  t.after(async () => { await close(tester); rmSync(root, { recursive: true, force: true }); });
+  const viaTester = (path, method = 'GET') => new Promise((resolve, reject) => {
+    const req = request({ socketPath: socket, path, method, headers: { host: 'mosaic-tester.invalid' } }, res => { res.resume(); res.on('end', () => resolve(res.statusCode)); });
+    req.on('error', reject); req.end();
+  });
+  for (const path of ['/system-types.js', '/system-types.css']) assert.equal(await viaTester(path), 403, path);
+  // The tester has no organization session, so the per-organization routes answer org-unavailable.
+  for (const [path, method] of [[ORG, 'GET'], [ORG, 'POST'], [`${ORG}/projects/p1`, 'GET']]) assert.ok([403, 404].includes(await viaTester(path, method)), path);
+  const plain = await startServer({ port: 0, organizations, log: () => {} }); t.after(() => close(plain));
+  const plainBase = `http://127.0.0.1:${plain.address().port}`;
+  assert.ok((await fetch(`${plainBase}${ORG}`)).status >= 400);
+  // The owner's dev session on a Console with the routes: the file is served.
+  const owner = await startServer({ port: 0, sso: createDevOwner(), send: async () => ({}), organizations, log: () => {} }); t.after(() => close(owner));
+  assert.equal((await fetch(`http://127.0.0.1:${owner.address().port}/system-types.js`)).status, 200);
+  assert.equal(reached, 0);
+  await assert.rejects(startServer({ port: 0, sso: createDevOwner(), systemTypesWrite: hit, log: () => {} }), /System types writes need/);
+});
@@ -6,11 +6,13 @@ import { createOrgAdmin } from '../src/org-admin.mjs';
 import { browser } from './browser.mjs';
 import { close } from './fixture.mjs';
 import { fileURLToPath } from 'node:url';
+import { systemTypesFake } from './helpers/system-types-fake.mjs';

 const waitFor = b => expression => b.evaluate(`(async()=>{for(let i=0;i<150;i++){if(${expression})return;await new Promise(r=>setTimeout(r,30))}throw Error(${JSON.stringify(expression)})})()`);

-// Three organizations as sample 01 and 03 show them: two running buses and one stopped.
-function workspaceOrgs({ failThreads = false, seen = null } = {}) {
+// Three organizations as sample 01 and 03 show them: two running buses and one stopped. P2: each running
+// organization's System types read comes from the installed modules; `send` adds the owner's writes.
+function workspaceOrgs({ failThreads = false, seen = null, send = false, types = {} } = {}) {
  const ORGS = [
    { id: 'ddigital', label: 'Distinctly Digital', theme: 'rosewood', busHealthy: true },
    { id: 'forge', label: 'Forge', theme: 'cobalt', busHealthy: true },
@@ -24,6 +26,8 @@ function workspaceOrgs({ failThreads = false, seen = null } = {}) {
  const AGENTS = { ddigital: [{ role: 'chief', holder_run: 'r1', state: 'waiting' }, { role: 'copywriter', holder_run: 'r2', state: 'working' }], forge: [] };
  const claim = (thread, holder_run) => ({ thread, holder_run, harness: 'claude', at: '2026-11-09T12:00:00.000Z' });
  const CLAIMS = { ddigital: [claim('t3', 'r1'), claim('t1', 'r2'), claim('t2', 'r3')], forge: [] };
+  const TYPES = { ddigital: { enabled: ['coding', 'marketing'], projects: { 'spring-launch': ['coding'], 'brand-refresh': ['marketing'] } }, forge: { enabled: [], projects: { 'api-gateway': [] } }, ...types };
+  const fakes = {};
  const FILES = { 'spring-launch': ['docs/north-star.md', 'docs/launch-plan.md', 'src/index.js'], 'brand-refresh': ['docs/brand-voice-guide.md'], 'api-gateway': [] };
  const instances = id => ({ business: id, revision: 'a'.repeat(64), launch: true, noHire: [], retired: [], definitions: {},
    instances: Object.fromEntries(Object.entries(INSTANCES[id]).map(([n, [definition, running]]) => [n, { definition, vars: {}, launched: true, launcher: false, protected: false, kept: false, running, alive: [] }])) });
@@ -35,8 +39,10 @@ function workspaceOrgs({ failThreads = false, seen = null } = {}) {
      seen?.push(id);
      const org = ORGS.find(o => o.id === id); if (!org) return null;
      if (!org.busHealthy) return { busHealthy: false, reads: null, bus: {}, chat: { projects: async () => [], threads: async () => [] } };
+      fakes[id] ??= systemTypesFake(TYPES[id]);
+      const st = await fakes[id];
      return {
-        busHealthy: true,
+        busHealthy: true, requestRead: st.requestRead, systemTypesWrite: send ? st.systemTypesWrite : null, ...(send ? { send: async () => ({}) } : {}),
        reads: { business: async () => business(id), settings: async () => ({ release: '0.0.42', notifier: { binding: 'discord' }, launch: { limits: { total: 4 } } }),
          queue: async () => ({ rows: id === 'ddigital' ? [{ state: 'done' }, { state: 'in-progress' }, { state: 'queued' }] : [] }), busStatus: async () => ({}) },
        bus: { instances: async () => instances(id), messages: async () => ({ messages: [], unread: 0 }), agents: async () => AGENTS[id], 'thread.claims': async () => CLAIMS[id], inbox: async () => [], tasks: async () => [] },
@@ -110,13 +116,8 @@ test('sidebar follows sample 01 and Queue opens from the organization dashboard,
  assert.equal(queue, '#/queue');
  await b.evaluate('document.querySelector("[data-org-queue]").click()');
  await wait('location.hash === "#/orgs/ddigital/queue" && [...document.querySelectorAll("#bus-view h1")].some(h => h.textContent.trim() === "Queue")');
-  // Views not built yet open and say so.
-  // Inbox (U3, workspace-pages-browser.test.mjs) and Tasks (U4b, tasks-board-browser.test.mjs) are built.
-  for (const [route, title] of [['side-by-side', 'Side by side']]) {
-    await b.evaluate(`location.hash = "#/orgs/ddigital/${route}"`);
-    await wait(`document.getElementById("bus-view").innerText.includes("not built yet") && [...document.querySelectorAll("#bus-view h1")].some(h => h.textContent.trim() === ${JSON.stringify(title)})`);
-    assert.doesNotMatch(await b.evaluate('document.getElementById("bus-view").innerText'), /error|failed/i, route);
-  }
+  // Every sidebar view is built: Inbox (U3, workspace-pages-browser.test.mjs), Tasks (U4b,
+  // tasks-board-browser.test.mjs) and Side by side (U5, side-by-side-browser.test.mjs).
 });

 test('organization dashboard renders every section from the per-organization reads', async t => {
@@ -130,7 +131,8 @@ test('organization dashboard renders every section from the per-organization rea
  assert.equal(head.avatar, 'DD'); assert.equal(head.title, 'Distinctly Digital');
  assert.match(head.meta, /Kind not recorded/); assert.match(head.meta, /id ddigital/); assert.match(head.meta, /Tracker: Vikunja/); assert.match(head.meta, /bus running, read \d/);
  assert.match(head.colour, /^#[0-9a-f]{6}$/i);
-  assert.match(await b.evaluate('document.querySelector(".ws-typechips").innerText'), /System types\s+No system types yet/i);
+  // System types: the enabled modules by their own labels (P2).
+  assert.match(await b.evaluate('document.querySelector(".ws-typechips").innerText'), /System types\s+Coding\s*Marketing\s+Each project picks from these/i);
  // Docs come from the project files reads: only documents, named by project.
  assert.deepEqual(await b.evaluate('[...document.querySelectorAll(".ws-doc")].map(a => a.innerText.replace(/\\s+/g, " ").trim())'), ['North star Spring launch', 'Launch plan Spring launch', 'Brand voice guide Brand refresh']);
  // KPIs and metrics: one honest empty tile each, with no invented number.
@@ -155,7 +157,8 @@ test('organization dashboard renders every section from the per-organization rea
  for (const s of settings) { assert.ok(s.icon, s.name); assert.ok(s.value, s.name); assert.ok(TAGS.includes(s.tag), `${s.name}: ${s.tag}`); }
  const by = Object.fromEntries(settings.map(s => [s.name, s]));
  assert.deepEqual([by['Members and invites'].tag, by['Members and invites'].href], ['not built', null]);
-  assert.deepEqual([by['System types'].tag, by['System types'].href], ['not built', null]);
+  assert.deepEqual([by['System types'].tag, by['System types'].value], ['org file', '2 of 5 installed enabled']);
+  assert.equal(await b.evaluate('document.querySelector(\'[data-org-setting="System types"] button.go\').textContent'), 'Open');
  assert.deepEqual([by['Archive or delete'].tag, by['Archive or delete'].danger, by['Archive or delete'].href], ['danger', true, '#/settings/organizations']);
  assert.equal(by.Identity.value, 'Distinctly Digital · ddigital · kind not recorded');
  assert.equal(by['Task tracker'].value, 'Vikunja');
@@ -175,7 +178,8 @@ test('organization dashboard empty states say so in one short line', async t =>
  await waitFor(b)('document.querySelector("[data-org-dashboard] [data-org-settings]")');
  const text = await b.evaluate('document.querySelector("[data-org-dashboard]").innerText');
  // Section labels are uppercased by CSS, so innerText carries the uppercase form.
-  for (const line of [/System types\s+No system types yet\. They arrive with the system types update\./i, /Docs\s+No docs yet/i, /No KPIs defined in the organization file/, /No metrics recorded yet/, /Active agent sessions\s+none running/i, /No active agent sessions/, /Queue\s+no rows/i, /Tracker: not set/])
+  // The empty organization has no System types read, so it says unavailable, never that none exist.
+  for (const line of [/System types\s+System types unavailable/i, /Docs\s+No docs yet/i, /No KPIs defined in the organization file/, /No metrics recorded yet/, /Active agent sessions\s+none running/i, /No active agent sessions/, /Queue\s+no rows/i, /Tracker: not set/])
    assert.match(text, line);
  assert.equal(await b.evaluate('document.querySelectorAll("[data-org-settings] > li").length'), SETTINGS.length);
 });
@@ -8,6 +8,7 @@ test('integrated project settings and conversation mounts use authorized context
    [`GET /api/chat/rooms/${ids.project}/messages?limit=100`]: {status:503,body:{error:'fixture-unavailable'}},
    'GET /api/project-files?project=fixture-repository': {status:503,body:{error:'fixture-unavailable'}},
    'GET /api/project-file?project=fixture-repository&path=spec%2Fnorth-star.md': {status:503,body:{error:'fixture-unavailable'}},
+    [`GET /api/system-types/projects/${ids.project}`]: {status:503,body:{error:'fixture-unavailable'}},
    '/api/project-remotes/fixture-repository': { project: ids.repository, remote: null, revision: 'a'.repeat(64), firstSaveAllowed: true },
  };
  const { f, b, wait } = await w15Fixture(t, { scenario });
Author	SHA1	Message	Date
jason.woltje	200b30b721	fix(webui): P2 system types in a side-by-side pane only show, never switch (#1873 ) U5 draws the organization dashboard into a side-by-side pane, and the System types section came with it: Enable and Disable buttons that wrote to the selected organization whatever the pane showed, a heading id repeated in both panes, and a Settings Open button that focused the first pane's section. A pane now shows its own organization's types with no switch and says to change them from the full view, as U5 does for the bus restart. The heading id carries the pane's prefix, Open focuses the section in its own dashboard, and the click handler and the post-write repaint ignore panes.	2026-11-10 14:44:02 -06:00
jason.woltje	ff74bde424	test(webui): answer the project system-types read in the W15 integration fixture (#1873 )	2026-11-10 14:41:53 -06:00
jason.woltje	85e9fcd894	fix(webui): P2 review fixes for system types (#1873 ) Recheck the session after the read so a sign-out dispatches no write. Take the enabled set and its revision from one plugins read. Let the owner clear an inactive-only selection when nothing is enabled. Keep role tools as the hard ceiling in the toolset design, name only vocabulary tools in the mapping, and intersect mission and task over the final set.	2026-11-10 14:41:53 -06:00
jason.woltje	fec416d1df	feat(webui): P2 system types on the org dashboard and project page, toolset design (#1873 ) The org dashboard lists the installed system-type modules with their own labels and descriptions, marks which are enabled, and gives the owner an enable or disable control through plugins.set behind the owner fence, with the revision and the transaction receipt. The project page selects from the organization's enabled set through project.system-types.set and shows a disabled selection as inactive, as system-types.console reports. Both routes go through the per-org Console call path and its admission checks. docs/plans/2026-11-10_system-type-toolsets-design.md proposes how a launch turns a project's active system types into toolsets under the role, mission and task ceilings. Design only; no roles/ or contract change is applied.	2026-11-10 14:41:53 -06:00
jason.woltje	52a82a4e56	test(webui): U5 Agents panes keep their own project choice (#1873 ) The rebase onto U3 brought in A1's "Available in a project" chooser. Its change handler kept one renderer and wrote into the first table in the document, keyed by the page's organization. The rebase resolution keys the renderer and the choice by each grid's organization and redraws the table in the chooser's own section. This test covers it: before that change, pane b's choice never redrew pane b.	2026-11-10 14:07:05 -06:00
jason.woltje	5f3706e807	fix(webui): U5 pane view state survives a project repaint (#1873 ) A pane keeps its request choice and PRD disclosure on the pane, per organization, instead of on the project content element. A new conversation changes the project header, which replaces that element; the choice now survives it.	2026-11-10 14:07:05 -06:00
jason.woltje	5f57008aed	fix(webui): U5 review fixes for side by side panes (#1873 ) One observer per pane element, disconnected on leaving the page, so a closed and reopened pane rewrites links for its current organization. Project reads check the pane generation and organization before any DOM write. Request selection and expanded PRDs are kept per pane. A late navigation focuses its heading only when focus has not moved to the other pane. Project pages in a pane use a compact layout with container queries.	2026-11-10 14:07:05 -06:00
jason.woltje	bc3e0a9f49	feat(webui): U5 side by side, two panes across organizations and projects (#1873 ) The Side by side page now opens two panes. Each pane shows an organization dashboard, an agents grid or a project page, chosen from a picker that lists every organization and project. Pane state lives in the URL and is kept per viewer. A separator resizes the panes by pointer or arrow keys, closing a pane goes back to one, and each pane keeps its own focus and scroll through polling. A pane whose organization's bus is down says so while the other pane keeps working. On a phone a two-way switch shows one pane at a time. Panes are read-only. Conversation, room, settings, queue, docs and inbox pages open in full view; chat.js is a single-instance page with global ids.	2026-11-10 14:07:05 -06:00