feat(channels): restore tab workspaces across refresh - #1793

…2562)

## Summary

Closing a routed panel tab calls `history.go(-1)` to retire its visit,
and that return lands on a later popstate. Until it lands, the navigator
still shows the closing visit, but the opener already has focus. If a
Profile was reopened from the opener in that window, it was hidden when
the return arrived, because entering the channel visit restored that
visit's saved selection. This PR treats a reopen made before the return
lands as superseding the close, so the panel stays open with a fresh
visit of its own.

### fix(channels): keep a panel reopened before its close's return lands

**Problem**

Two WebKit journeys lost a Profile that was reopened right after its tab
closed. Both failed on attempt 1 on unrelated branches, and the same SHA
passed on rerun.

- `profiles.spec.mjs:321` "profile plumbing: exact avatar/mention
targets, thread enrichment, lifecycle and recovery", branch
peon/participant-collator, run 41752442750 (webkit 13/14):
https://github.com/block/buzz-app/actions/runs/41752442750/job/126320885261.
After the Mic tab closed, Space on the focused mention never reopened
the Profile, and the test failed at :479.
- `solo-workspace.spec.mjs:159` "Solo chat Activity opens the agent's
profile locally, restores per conversation and retires on plugin
disable", branch peon/dnd-stable-transform, run 41757728323 attempt 1
(webkit 5/14):
https://github.com/block/buzz-app/actions/runs/41757728323/job/126338025674.
After the agent's Profile closed, Enter on the focused Activity trigger
never brought back "Profile details".

**Cause**

- Closing a routed panel tab removes it locally. `dismissContent` then
calls `navigator.dismiss`. The browser driver retires the visit and
calls `history.go(-1)`, which lands on a later popstate. Until then the
navigator still shows the retiring visit, while `afterClose` has already
focused the opener.
- A reopen in that window runs `open()` and then `visitPanel`.
`visitPanel` sees the navigator already on that Profile's detail, so it
doesn't navigate. When the return lands, the route effect enters the
channel visit, and `enterVisit` restores that visit's saved selection,
which hides the reopened panel. Reopening a different panel pushes its
visit on top of the retiring one, and the late return then removes it.
- Both traces show this sequence:
- Profiles run: the close finished at 80128 ms and Space ran at
80148–80193 ms with the URL still on Mic's detail. By 80383 ms the URL
was the channel and the dock was closing.
- Solo run: the close finished at 251783 ms and Enter ran at
251808–251872 ms. By 251999 ms the URL was the channel and the dock was
hidden.
- The dock isn't the cause. `PanelDock` keeps a reopened subtree through
its exit (`PanelDock.test.tsx`).

**Fix**

- When a dismissal retires the current visit and the navigator hasn't
moved yet, `dismissContent` records a pending return. A synchronous
driver or a replacing dismissal moves the navigator at once, so neither
records anything.
- While that return is pending, `visitPanel` records the panel as the
reopen instead of navigating.
- When the return lands on the dismissal's fallback, the route effect
checks whether that panel is still selected. If it is, the effect
reselects and opens it, which gives it its own visit. If the panel has
closed again, or the return landed somewhere else, nothing is revived.
- A later close before the return lands, such as closing the thread
beneath a closed Profile, moves where the return lands. The record
follows the latest fallback and keeps the reopen.
- While the return is pending, the route effect no longer reapplies the
retiring visit's detail. Otherwise a re-render could reopen the panel
that was just closed.
- Two new cases in `profiles.spec.mjs` hold `history.go` and pause the
dock's exit while a Profile closes. One reopens Mic by click and by
Space. The other closes a thread's Profile and then the thread, and
opens Mic. Each asserts that the Profile shows while the return is held,
the navigator stays on the closed visit with exactly one return held, a
fresh Mic visit lands after the release, and Back returns to the channel
and closes the panel.

The existing journeys are unchanged, and no assertions are loosened.

**Residual limit**

Thread and other explicit navigation during a pending return is not
deferred, so a late return can still undo it. #2113 lists the same
limit.

**Validation**

Local Linux workstation, Playwright 1.63.0, `--no-deps --retries=0`:

- New cases without the fix: 4/4 failed. The reopen case failed at :406
(no fresh visit). The thread case failed at :442, with the click
stacking a visit on the closed one. With the fix but without the
latest-fallback step, the thread case failed 2/2 at :452. With the fix,
all pass.
- Adversarial ordering, with temporary changes that delayed `history.go`
calls from click or key handlers by 250 ms, 6 repeats per engine:
  - Without the fix: 9/24 failed, seven with the CI signatures.
  - With the fix: 24/24 passed, twice.
- Natural contention, with 4 CPUs shared with 4 busy loops, 2 workers
and 10 repeats per engine: 40/40 passed with the fix.
- The 38 browser specs that close panel tabs, both engines: all passed
at 6 workers. At 12 workers, 42 failed on timeouts because the test
server had stopped serving under load, and those 42 passed on rerun.
- Vitest for channels, panels, navigation and channel-navigation: 87
files, 1539 tests passed.
- Rebased on main `f4805605f5`:
- `tsc --noEmit`, `biome check --error-on-warnings` on the changed files
and `git diff --check` are clean.
  - Vitest `src/bundled/channels`: 61 files, 1097 tests passed.
- `profiles.spec.mjs` and `solo-workspace.spec.mjs` in full, WebKit and
Chromium, `--workers=4 --retries=0`: 48/48 passed.

A green run doesn't prove the flake is gone. Hosted CI covers broad
validation.

## Coordination

- #2415 (open) rewrites the same route effect in `ChannelsPage.tsx`
around a `dismissalReturn` record. Its head `9555c2ed` conflicts
textually with this branch. Whichever PR lands second should fold this
PR's pending `reopen`, and the guard against reapplying the retiring
visit's detail, into the other's record.
- #2113 (open) restores panel opener focus after history returns. It
doesn't overlap these hunks, its head merges cleanly with this branch,
and it lists the same residual limit described above.
- Draft #1793 (stale since 2026-10-29) also edits `ChannelsPage.tsx`,
and its head conflicts textually with this branch.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Signed-off-by: mtoohey <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>

…2803)

## Problem

Close all tabs (right-click a tab, ⌘⇧W, or the macOS **Close All Tabs**
menu item) closes the whole right pane. A launcher's side panel such as
Todos goes with it, even though it isn't a tab.

- Its launcher still reads pressed (`aria-expanded="true"`), so the
first press "closes" the hidden panel and nothing visible happens. Only
the second press brings Todos back.
- **Toggle tab pane** and **Back** to the channel visit end the same
way: Todos is hidden and the launcher reads pressed. Close all tabs from
that earlier channel visit also hides Todos.

## Fix

Close all tabs now leaves a launcher's side panel as it was: shown in an
open pane, hidden in a closed one. The launcher reads pressed only while
the pane shows the panel, so one press always brings it back. Production
change: 23 lines added and 5 removed, in 4 files.

1. **`closeTabs`** (`useChannelTabState.ts`): `paneOpen: side ||
(s.paneOpen && !!s.sidePanel)`. A pane showing a launcher's panel stays
open, and a closed pane stays closed.
2. **`onCloseTabs`** (`ChannelsPage.tsx`): when nothing is kept and a
launcher's side panel is selected, shown or hidden, it dismisses toward
the `"side"` pane, not `"main"`.
- `dismissContent` then records the existing side-panel survivor from
#1767, so the return to the channel visit keeps Todos. That's the same
path that keeps Todos when its last tab closes with X.
- The kept-return marker records the pane's pre-close visibility: a kept
tab shows, and a side panel keeps `paneOpen` as it was. The matching
return applies it after `enterVisit`, so a channel visit that saved an
open pane (a retained thread or Todos was in it) doesn't reveal the
Todos the user had hidden before ⌘⇧W.
3. **Launcher `pressed` and `toggle` via `shown`**
(`useChannelPanels.tsx`): a side panel counts as `shown` only while the
pane is open, and `pressed` and `toggle` use `shown`.
- On a hidden panel, one press goes through `onOpen`
(`setPaneOpen(true)`) and shows the pane with the panel.
- `selected` is unchanged, so the panel stays retained while the pane is
hidden.
- `ChannelPanelTabs` gains `paneOpen`. `useConversationTabs.tsx` passes
`tabState.paneOpen`, the flag its tab-placed `pressed` already reads.

Close other tabs on a main-pane tab now keeps the side panel beside it
too.

**Preserved:**
- [Navigation
history](https://github.com/block/buzz-app/blob/main/docs/navigation-history.md):
closed thread visits are still retired together. Back and Forward still
skip them, and no visit's saved pane state changes. Back to a channel
visit still restores that visit's saved pane. Where it was hidden, Todos
stays hidden, but the launcher now reads unpressed and one press shows
it.
- No visual change. Pressed now matches what's on screen.

**Docs:**
- `shell-design.md` describes Close all tabs and hiding the pane for
side panels.
- `plugin-architecture.md` defines `pressed` for `channelPlacement:
"side"` as "shown in the open pane", not merely selected.

## Tests

**Vitest** (`useConversationTabs.test.tsx`; `launcherHarness` gains a
`placement` parameter):
- "Close all tabs leaves a launcher's side panel as the open/closed pane
showed it":
  - The open case fails on main.
- The closed case fails if `closeTabs` drops the `s.paneOpen &&` guard.
- "a side panel's launcher reads unpressed while the closed pane hides
it, and one press shows it": catches the launcher change.
- "Close other tabs on a main-pane tab keeps a launcher's side panel
open beside it."

**Journey** (`tests/browser/todos.spec.mjs`): "Todos isn't a tab: Close
all tabs keeps it, and its launcher tracks the pane". This is one new
browser case; none were removed.
- **Why it needs a browser:** Close all tabs retires the thread's
history visit, and the page's return to the channel visit has to keep
the side panel. jsdom page tests don't route visits through navigation.
- **What it covers:**
1. Toggle tab pane hides Todos with the launcher unpressed, and one
press shows it.
  2. Close all tabs from a thread visit keeps Todos.
3. Back to a channel visit that saved a closed pane hides Todos, one
press shows it, and Close all tabs from there keeps it. Since #2838 a
channel visit showing Todos saves an open pane, so the journey hides the
pane there first.
4. ⌘⇧W from a thread visit with the pane closed doesn't reveal Todos,
even when the channel visit it returns to saved an open pane.
- **What fails without each part:**
  - On main, it fails at the first launcher check after Toggle tab pane.
- With the `closeTabs` change reverted, it fails at Close all tabs from
the channel visit.
  - With only the launcher change, Todos is gone after Close all tabs.
- If the return drops the kept-return marker's `paneOpen`, it fails at
the ⌘⇧W step from a closed pane.

**Fail before, pass after:**
- With only the first commit's tests applied to main, Vitest fails 2 of
42. The journey fails in Chromium and WebKit, where `aria-expanded` is
"true" after Toggle tab pane.
- With the fix:
- 139 Vitest tests pass across `useConversationTabs`,
`useConversationTabs.panels`, `useChannelPanels`, `useChannelTabState`
and `ChannelsPage.tabs`.
- `todos.spec.mjs`, `tab-close-others.spec.mjs` and
`right-pane-dismissal.spec.mjs` pass in Chromium and WebKit, 32 tests in
all. So does the layout.spec case "Todos stacks beside threads".
  - `tsc --noEmit` and `biome check --error-on-warnings` are clean.
- These local runs were on the same three patches before the rebase onto
067db60. That rebase brought in only #2587 (inbox, thread and unread
files), which touches none of this PR's files. The later rebase onto
be67480 brought in #2838 (retained side panels); the journey's Back
setups were reconciled with it in 2a30ea9 and have not been run
locally since.

## Not checked

- The native ⌘⇧W menu. The browser runs dispatch `buzz:close-all-tabs`,
the window event the native menu sends. The page handled it
(`preventDefault`), and the result matched the right-click menu.
- The desktop app.

## Related

- **#2415** reworks the same dismissal-return code. This change depends
on `dismissContent` keeping `(pane === "side" && tabState.sidePanel)`.
Whichever of the two lands second must keep that condition.
- **#1793** (draft, conflicting) rewrites `closeTabs` and changes
`onCloseTabs`. If it's revived, it needs the same two rules:
  - A pane showing a launcher's side panel stays open on Close all tabs.
- `onCloseTabs` dismisses toward the side pane while a launcher's side
panel is selected, and the return reapplies the pane's pre-close
visibility.

## Before and after

Both runs used the same scripted steps on the same timeline. Each run
checked the expected state at every step, and both passed.

| Step (starts at) | Before: main @ 3bcf1c4 | After: this branch @
2c81a4905 |
|---|---|---|
| 1. Press **Toggle channel todos**, then open the thread from its reply
chip (3.6 s) | Thread tab above Todos. Launcher pressed. | Same. |
| 2. Right-click the thread tab, choose **Close all tabs**, hold about
3.5 s (10.0 s) | The whole pane closes, and Todos goes with it. The
launcher still reads pressed, so the badge turns red. | The tab closes.
Todos stays and fills the pane. Launcher pressed. |
| 3. Open the thread again, then ⌘⇧W (16.2 s) | Reopening brings back
the thread with Todos, because Todos was never deselected. ⌘⇧W then
hides both, and the launcher still reads pressed. | ⌘⇧W closes the tab
and Todos stays. Launcher pressed. |
| 4. Open the thread again, then **Toggle tab pane** (23.2 s) | Pane and
Todos hidden. Launcher **still pressed**. | Pane and Todos hidden.
Launcher **not pressed**. |
| 5. Press the Todos launcher once (30.0 s) | Nothing visible happens.
The launcher flips to not pressed and Todos stays hidden. | The pane
comes back with the thread tab above Todos. Launcher pressed. |

2c81a4905 has the same fix and tests as this PR, from before the rebase.
The only later commit changes a comment and docs. The video was recorded
in Chromium against the fixture relay, with ⌘⇧W sent as the
`buzz:close-all-tabs` event. Back, and Close all tabs from the earlier
channel visit, are covered by the journey but not shown in the video.


https://github.com/user-attachments/assets/c40bd79d-7668-4511-b065-915e533ea6e6

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Signed-off-by: mtoohey <[email protected]>
Signed-off-by: Matt Toohey <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>

…l switches (#3060)

## Why

Since #2838 keeps a channel's side panels open when you return to it,
the GitHub tab survives a channel switch but its panel is unmounted and
remounted. Coming back to the channel therefore started the pull request
panel over: **Changes** fell back to **Summary**, and a **Submit
review** draft (decision, text, and the head it was written against) was
lost.

## What changes

The GitHub plugin owns a small per-session panel memory, created once in
`apply` beside the pull-state store
(`src/bundled/github/panel-memory.ts`):

- **View** (Summary/Changes) is remembered per channel + pull request
URL. A first open from another channel starts on Summary with the title.
- **One review draft per pull request URL**, from any channel, matching
GitHub's one pending review per pull request.
- The draft **leaves memory when a submit starts** and **returns only if
the submit fails** (unless another panel has started a new draft since).
A panel remounted mid-submit, or a second tab on the same pull request,
cannot offer the in-flight review again. `Use latest commit` is disabled
while a submit is in flight and the write effect skips while busy.
- **Text-less decisions are not remembered.** A Request changes or
Approve with no comment stays in the mounted panel only.
- A **text-less Approve still sees the "New commits were pushed"
notice** after a push, with Submit disabled, as on main. Only an empty
Comment silently follows the latest head.
- Memory lasts the **app session** per plugin activation: a reload or
turning the plugin off and on forgets it.
- **Scroll position is not restored**; that needs a host change.

`docs/buzz-help.md` gains a bullet describing this.

#1793 (restore tab workspaces across refresh) is rebase-only against
this; there is no behavioural interaction.

## Before and after

Before is on the left at `origin/main` `a905c4865f` (the fix commit's
parent); After is on the right at `a5ad4ba667`. Watch the GitHub panel
on the right of each half.


https://github.com/user-attachments/assets/713b8646-29e0-4447-a96b-5b27b8a58a72

![Caption 7, reopening Submit review after the round trip: Before opens
an empty Comment with Submit disabled; After reopens on Request changes
with the typed sentence and the diff still behind
it.](https://github.com/user-attachments/assets/2c56a70a-0cc6-4c60-b811-5399ef10653a)

| Moment | Before (`a905c4865f`) | After (`a5ad4ba667`) |
|---|---|---|
| Open the PR from a message link in #Alpha, switch to Changes, open
Submit review, choose Request changes, type a sentence, Escape, switch
to #Beta | Same on both sides | Same on both sides |
| Back in #Alpha (~15 s) | **Summary**, description from the top, no
diff | **Changes** selected, diff showing |
| Reopen Submit review (~18 s) | **Comment**, empty box, Submit disabled
| **Request changes** with the sentence, Submit enabled |
| Submit (After) or Escape (Before) | Nothing to submit | Submits;
"Review submitted" toast |
| #Beta and back, reopen Submit review | Empty Comment | Empty Comment:
the sent draft is gone |

The recording is the production browser build with the plugin's `gh`
client and diff reader swapped at build time for an in-memory stub so
Changes and Submit review are available outside the desktop app; nothing
else is faked.

## Test plan

- `GitHubPanel.test.tsx` 52 → 60 passing; GitHub plugin suite 345 → 355
passing across 21 files. `tsc --noEmit` clean; Biome clean on changed
files.
- Each new test was confirmed to fail with its fix removed: the remount
case on main; the mid-submit remount cases without the clear-at-start /
put-back-on-failure; the fresh-open-from-another-channel case with a
view keyed by URL alone; the whitespace-only draft case with the old
empty rule; the text-less Approve push case without the head rule; the
two-panel case without the re-read branch; the mid-submit push case with
the busy guards removed.
- Not checked by hand in the desktop app with `gh` signed in.

## Known limits

- Two tabs on the same pull request share one draft; the last one to
type wins and the other panel takes over the draft when its popover
reopens.
- Closing a tab on purpose and reopening the pull request in the same
channel still restores the remembered view.
- A draft on a pull request that merges or closes first lingers unseen
until the session ends, since Submit review goes away once closed.
- No scroll restore.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Signed-off-by: mtoohey <[email protected]>
Signed-off-by: Matt Toohey <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>