[teamleaderleo]

cmux-next checks fails on feat-cmux-next at check-scrollbars: 13 hits over its ceiling of 10. Three are web rules hiding a scrollbar, which SCROLLBARS-THIN forbids (scrollbar-width and ::-webkit-scrollbar turn WebKit's overlay scroller into a custom one):

• threadMinimap.css: the minimap list (cmux-next agent pane: the minimap lights where you are and the message it previews #22879) set scrollbar-width: none and ::-webkit-scrollbar { display: none }.
• pages/apps/styles.css: the narrow Discover chips strip set scrollbar-width: none.

Both now keep the shared thin overlay scroller, hidden until the user scrolls. The minimap keeps its edge fades and overscroll-behavior: contain. Removing only the minimap's two would leave 11, still over the ceiling, so the chips line goes too. The check is now at 10 (warnings only; the rest are Swift ratchet debt).

Tests

• SCROLLBARS_WARN_MAX=10 scripts/cmux-next/check-scrollbars.sh on this branch: passes (10 warnings), and on feat-cmux-next it fails (13 hits).
• No test or gallery asserts these scrollbars are hidden.

No capture: webview CSS only; a scroller that shows only while scrolling, no change at rest.

Agent session: cosmic-gray

🤖 Generated with Claude Code

---

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

---

Summary by cubic

Fixes the cmux-next check-scrollbars failure (13 hits over its ceiling of 10) by stopping the minimap rail and Apps Discover chips from hiding their scrollbars.

Both hid them with scrollbar-width: none and, for the minimap, ::-webkit-scrollbar { display: none } — rules that turn WebKit's overlay scroller into a custom one, which SCROLLBARS-THIN forbids. They now keep the shared thin overlay scroller, hidden until the user scrolls, so there's no visual change at rest. The minimap keeps its edge fades and overscroll-behavior: contain; the check drops to 10 warnings.

Tests

• SCROLLBARS_WARN_MAX=10 scripts/cmux-next/check-scrollbars.sh passes on this branch and fails on feat-cmux-next (13 hits).
• No test or gallery asserts these scrollbars are hidden.

^{Written for commit 3ca83c7. Summary will update on new commits.}

[teamleaderleo]

Owned by subsession-visibility-2 on cosmic-gray · session

[teamleaderleo]

Review (independent Claude subagent, subsession-visibility-2): SHIP at 3ca83c7

check-scrollbars passes (10 Swift ratchet-debt warnings, no hard failure). Both pages install the shared scroller CSS (pages/shared/desktop → installScrollers), so the rule removal is the fix the check asks for, not an exception. No test, gallery or snapshot depends on the hidden scrollbars (headless Chromium hides scrollbars anyway).

Follow-up, not blocking: with macOS "Show scroll bars: Always", a compact minimap rail that overflows draws an 8px legacy scroller over the right end of its 36px ticks, covering the bookmark dot's hit area. Overlay mode (the default) is unaffected. A follow-up can widen the rail by --cmux-scroller-size under data-scrollers="legacy".

Agent session: cosmic-gray

[blacksmith-sh]

Found 15 test failures on Blacksmith runners:

Failures

Test	View Logs
/tmp/tmpmgeutcnb/summary-fail.json (live):/summary-fail.json (live):	View Logs
/tmp/tmpyjq5x2nt/summary-missing.json (live):/summary-missing.json (live):	View Logs
convention violations found (ERROR lines above)./ convention violations found (ERROR lines above).	View Logs
test/agent-pane-math.test.tsx/agent-pane-math.test.tsx	View Logs
test/agent-pane-math.test.tsx/agent-pane-math.test.tsx	View Logs
test/agent-pane-scrollbar-full-height.test.ts/agent-pane-scrollbar-full-height.test	View Logs
test/agent-pane-scrollbar-full-height.test.ts/agent-pane-scrollbar-full-height.test	View Logs
test/home-composer-menu.test.tsx/home-composer-menu.test.tsx	View Logs
test/home-composer-menu.test.tsx/home-composer-menu.test.tsx	View Logs
test/home-quote-selection.test.tsx/home-quote-selection.test.tsx	View Logs

...and 5 more test failures. View all on Blacksmith: run 39580790764, run 39580781911

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

[github-actions]

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

Unclear: web / react-apps-check (3) failed: no known signature; failed step: Test webviews. This PR merged before its CI finished: fix forward on main.

CI failed on 3ca83c7a27 (run 39580790764 attempt 1): 2 code, 2 unknown.

Job	Verdict	Why
web / react-apps-check (3)	unknown	no known signature; failed step: Test webviews
web / react-apps-check (1)	code	a Python test failed
web / react-apps-check (2)	code	a web test failed
web / react-apps-check	unknown	no known signature; failed step: Check webview test shards

Failures:

• seen on other PRs gallery-coverage.test.ts gallery coverage > the entries are valid: failed (job)
• seen on other PRs agent-pane-scrollbar-full-height.test.ts a composer that grows and shrinks leaves the rows a reader reads where they were on every frame: failed (job)
• seen on other PRs agent-pane-scrollbar-full-height.test.ts a composer that grows and shrinks keeps a followed view at its end on every frame: failed (job)
• seen on other PRs agent-pane-math.test.tsx each delimiter typesets once math appears: failed (job)
• seen on other PRs pane-english.test.ts agent pane strings > no user-visible English is written in the pane's sources: failed (job)

Matched log lines

web / react-apps-check (1): FAIL: test_coverage_base_gap_warns_on_a_pr_changing_the_gallery_format (__main__.ScopedChecksTests.test_coverage_base_gap_warns_on_a_pr_changing_the_gallery_format)
web / react-apps-check (2): (fail) each delimiter typesets once math appears [71.81ms]

Not re-run automatically: web / react-apps-check (3), web / react-apps-check (1), web / react-apps-check (2), web / react-apps-check are not machine failures.

Written by scripts/ci/classify_failures.py (ci-failure-attribution.yml); signatures are its SIGNATURES table. A machine verdict is the runner's fault, not this PR's; yours means the failing file is one this PR changes, also red on main that main's latest full suite fails the same way, seen on other PRs that it failed on another pull request's run lately.

red: cmux-next checks (god files, concurrency, crash safety, l10n); base red: the same failure on the base 0e51a06; does not block
red: web / Web status; NEW: green on the base 0e51a06; do not merge until green; see lane-rules
red: web / react-apps-check; no finished base run on 0e51a06 to compare; do not merge until green; see lane-rules
red: web / react-apps-check (1); no finished base run on 0e51a06 to compare; do not merge until green; see lane-rules
red: web / react-apps-check (2); no finished base run on 0e51a06 to compare; do not merge until green; see lane-rules
red: web / react-apps-check (3); no finished base run on 0e51a06 to compare; do not merge until green; see lane-rules

CI fast guards failed on 3ca83c7a27 (https://github.com/manaflow-ai/cmux/actions/runs/39580782047). It does not block the merge; a red guard merged into main breaks it for every open PR.
The log named no failed step; see the run.

Agents: python3 scripts/ci/guard_attribution.py fix applies the mechanical fixes locally.

Tour of 3ca83c7a27 (run): no media. The tour did not run: only webview code changed (2 path(s)), which the gallery advisory run checks in Linux Chromium on the pull request (its artifact holds any captures); add the media-tour-mac label to tour it on a Mac.

[teamleaderleo]

Bead cx-9b15h created for this PR by the cmux coordinator.

[teamleaderleo]

codex-review: SHIP at 3ca83c7

• Reviewed the current diff, focused tests, and affected call paths; no correctness bug found.

[github-actions]

Shipped in:

• cmux NEXT nightly 1.0.0-nightly.3959138489301 (fbcc11eb32)
• cmux NEXT nightly 1.0.0-nightly.3959266027401 (5f84bd023b)
• cmux NEXT nightly 1.0.0-nightly.3959297427901 (7b41b2a4e3)
• cmux NEXT nightly 1.0.0-nightly.3959546622601 (d8da22192e)