[teamleaderleo]

Leo, on a toast in the cmux NEXT sidebar: "the heck happened here?" The toast read:
"Collapse/Expand Workspace Group did not apply: update-personal-group: timed out: workspace_group.update (no reply within 2.0 seconds)".

What happened

Collapsing a group already showed the fold on the click (SidebarRows.fold). But when the daemon's reply to workspace_group.update missed the 2 s control deadline, the app treated the timeout as a failure: it dropped the fold, resynced the sidebar back to the old look and showed a "did not apply" toast, even though a timed-out command may still apply (ActionWorkFailure.mayHaveApplied). The daemon was slow to answer because the control channel was busy (idle personal.session.put churn; #33318 removed the identical saves at the source).

Fix

A fold is this window's look, so a slow save never undoes it or shows a notice:

• SidebarRowEdits.saveFold (CmuxNextSidebar) holds the fold and sends the save; a reply that only missed its deadline is sent again in the background with Backoff (about 0.5, 1, 2, 4 s; SidebarFoldPersist), with no toast.
• A later click on the same group stops the earlier fold's retries, so a stale value never overwrites the newer one.
• After the last retry the hold is released quietly; the store's next echo shows what the daemon holds.
• Only a real refusal (not connected, a rejected command) still drops the fold and reports, as before.
• SidebarRows.fold (App) shrinks to a call into it (App lines -6).

Loop stop conditions: the retry task ends at the first reply, a refusal, a later click on the group, cancellation, or after 4 retries (at most about 7.5 s of waits).

Design spec: sidebar (plans/cmux-next/sidebar-owner.md); no visual change.

Changelog

Fixed: Collapsing or expanding a workspace group no longer shows a "did not apply ... timed out" notice or snaps back when the background service is slow to answer.

Tests

SidebarFoldPersistTests (new): a slow reply is sent again with no report and settles on the reply; a refusal reports once with no retry; a save that never answers gives up quietly after every retry; a later click stops the earlier fold's retries. Run with GroupHeaderClickTests and SidebarHostGroupTests on the fleet (cmux-ci run --class light --script scripts/ci/package-test-lane.sh --arg=suite ...); result in a comment below.

Observed / Not run

• Observed: prepush gate clean; fleet suite run (see comment).
• Not run: a live repro of the slow daemon in a DEV build.

Agent session: agent session

🤖 Generated with Claude Code

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Summary by cubic

Fixes the cmux NEXT sidebar so collapsing or expanding a workspace group no longer shows a "did not apply ... timed out" notice or snaps back when the daemon is slow to answer.

The fold shows on the click; a save that misses the 2 s control deadline is retried quietly in the background (about 0.5, 1, 2, 4 s) with no toast. A later click on the same group stops earlier retries; after the last retry the hold is released quietly and the store's next echo shows what the daemon holds. Only a genuine refusal (not connected, a rejected command) still drops the fold and reports. SidebarFoldPersistTests cover retries, refusal, silent give-up, and a later click stopping earlier retries. CmuxNextWakeups is now imported publicly where Backoff appears in public signatures, and the test target depends on it.

^{Written for commit ac75c91. Summary will update on new commits.}

[github-actions]

cmux status _{(one comment, edited in place; each line is updated by the job that owns it)}

Review ac75c91: HQ feed card · gallery before/after runs · checks

App of this head (app.zip, kept 1 day)

gh workflow run reload-build.yml -R manaflow-ai/cmux --ref feat-cmux-next -f tag=pr34405 -f ref=fix--group-collapse-timeout -f platform=macos -f backend_mode=local

red: cmux-next checks (god files, concurrency, crash safety, l10n); base red: the same failure on the base 26fd471; does not block

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.4175186455101 (a7072f8788)

[blacksmith-sh]

Found 36 test failures on Blacksmith runners:

Failures

Test	View Logs
main.DeveloperIdAppTests.test_download_prints_the_active_profile_only/ test_download_prints_the_active_profile_only	View Logs
stubs: /System/Library/Frameworks/Security.framework/Versions/A/Security has no stub/ Security has no stub	View Logs
stubs: CoreFoundation.tbd: install-name /System/Library/Frameworks/ CoreFoundation.framework/Versions/A/CoreFoundation, missing 1: ['_CFRetain']/ CoreFoundation, missing 1: ['_CFRetain']	View Logs
stubs: CoreFoundation.tbd: install-name /System/Library/Frameworks/ CoreFoundation.framework/Versions/A/CoreFoundation, missing 1: ['_log2']/ CoreFoundation, missing 1: ['_log2']	View Logs
test_a_build_host_runs_every_piece_niced_and_capped (main.WebLintPrePushTests.test_ a_build_host_runs_every_piece_niced_and_capped)/ test_a_build_host_runs_every_piece_niced_and_capped (main.WebLintPrePushTests.test_ a_build_host_runs_every_piece_niced_and_capped)	View Logs
test_a_clean_pushed_commit_passes_whatever_the_working_tree_holds (main.WebLintPreP ushTests.test_a_clean_pushed_commit_passes_whatever_the_working_tree_holds)/ test_a_clean_pushed_commit_passes_whatever_the_working_tree_holds (main.WebLintPreP ushTests.test_a_clean_pushed_commit_passes_whatever_the_working_tree_holds)	View Logs
test_a_clean_swift_only_push_runs_only_the_pieces_that_read_it (main.WebLintPrePush Tests.test_a_clean_swift_only_push_runs_only_the_pieces_that_read_it)/ test_a_clean_swift_only_push_runs_only_the_pieces_that_read_it (main.WebLintPrePush Tests.test_a_clean_swift_only_push_runs_only_the_pieces_that_read_it)	View Logs
test_a_clone_with_no_reviewed_remote_lints_no_check_code (main.WebLintPrePushTests. test_a_clone_with_no_reviewed_remote_lints_no_check_code)/ test_a_clone_with_no_reviewed_remote_lints_no_check_code (main.WebLintPrePushTests. test_a_clone_with_no_reviewed_remote_lints_no_check_code)	View Logs
test_a_dry_run_lists_exactly_what_a_run_spawns (main.WebLintPrePushTests.test_a_dry _run_lists_exactly_what_a_run_spawns)/ test_a_dry_run_lists_exactly_what_a_run_spawns (main.WebLintPrePushTests.test_a_dry _run_lists_exactly_what_a_run_spawns)	View Logs
test_a_file_in_a_folder_above_a_package_is_check_code (main.WebLintPrePushTests.tes t_a_file_in_a_folder_above_a_package_is_check_code)/ test_a_file_in_a_folder_above_a_package_is_check_code (main.WebLintPrePushTests.tes t_a_file_in_a_folder_above_a_package_is_check_code)	View Logs

...and 26 more test failures. View all on Blacksmith

^{Need help on this PR? Tag @codesmith-bot with what you need.}

[teamleaderleo]

Review (subagent claude-opus-5-5 medium, correctness): SHIP at ac75c91
Visual verdict: unchanged by this diff
Checked: the refusal path still settles, resyncs and reports; an older settle never clears a newer click's fold; the test continuations resume exactly once. An earlier BLOCK at 70be1c3 (internal import of CmuxNextWakeups under InternalImportsByDefault) is fixed at this head.
Fleet: package-test-lane.sh suite Packages/macOS/CmuxNext SidebarFoldPersistTests,GroupHeaderClickTests,SidebarHostGroupTests at ac75c91: package compiled, 5/5, 2/2, 4/4 passed.
Follow-ups: [follow-up] giveUp settles without a quiet resync (sidebar may show an unapplied fold until the next echo); [follow-up] collapse/expand/collapse within one backoff window can send the first fold's retry alongside the third's save (same value, harmless).

[teamleaderleo]

Review (codex, router-review): SHIP at ac75c91

Reviewer: codex gpt-6-astra high, fast tier.

Follow-ups: 1. Each lands as an issue in this repo that links this receipt; the lane that opened the PR fixes it forward.

SHIP at ac75c91

Visual verdict: no images; Leo tries the build

1. [P1][follow-up] SidebarRowEdits.swift:78 records timeout failures in any active DaemonCommandScope through DaemonService.failure, before the retry policy handles them. Therefore action.run callers still receive the timeout from scope.failures even if a retry succeeds, contrary to the silent-retry behavior. Use a non-reporting path for may-have-applied timeouts and cover an action.run case. Swift tests could not run because this box has no Swift toolchain.

Follow-ups:

• [P1][follow-up] Suppress may-have-applied timeout failures from DaemonCommandScope settlement.

[lawrencecchen]

Swift logic follow-up (tip watcher swift-logic row, STATUS 13027 "SWIFT LOGIC CULPRITS"; lead order).

This PR raised swift_logic_lines by +50 at its merge commit 8aece82: scripts/cmux-next/swift-logic-lines.py before and after the merge, with the same table (the tip's, c6be943). The largest declarations of the rise:

• class SidebarRowEdits in Packages/macOS/CmuxNext/Sources/CmuxNextSidebar/Logic/SidebarRowEdits.swift: +37 lines counted as Swift logic (its row counts it as logic)
• enum SidebarFoldPersist in Packages/macOS/CmuxNext/Sources/CmuxNextSidebar/Logic/SidebarFoldPersist.swift: +19 lines counted as Swift logic (no row in plans/cmux-next/swift-logic-classes.tsv)

plans/cmux-next/layer-ownership.md says Rust owns every state, list and rule and Swift is the platform shell. Please move the new logic of this PR in a follow-up: to Rust (the crate that owns the area; the owner lists in STATUS 12147-12165 name the target per area), or at least out of the app into its package. If a declaration above is platform code (AppKit, Core Animation, OS calls, strings, tokens, DEBUG tooling), reply here and the table gets a PLATFORM row with your reason instead.

The swift-logic row is a report, not a gate: nothing blocks on this comment.