fix(web): stop the bar under the composer popping in after threads load

[t3dotgg]

Opening a thread whose messages were not cached painted the composer first, then the strip under it (env mode, branch, model and mode controls while resting) mounted a beat later and pushed the composer up. Subtle layout shift on most thread switches.

The strip read the thread through useThread, which stays null until the full thread detail (messages, activities) arrives. Every field it uses is on the thread shell, which the sidebar already renders from, so it is present before the route mounts. The strip, the branch selector, and the header git control now read the shell. The merge helper already treats the shell as the authoritative source for branch, worktree, and project, so this is the same data the detail path resolved to.

Created with Claude Fable 5.1 in Claude Code.

Summary by CodeRabbit

• Bug Fixes
  • Improved thread state loading in branch selection and Git actions.
  • Reduced delays when accessing server thread information, including scenarios involving draft sessions.
  • Preserved branch synchronization and live update behavior while making thread data available more directly.

[macroscopeapp]

Approvability

Verdict: Approved at 386cbef

Macroscope's review found this PR approvable — This is a narrowly scoped UI timing fix that makes existing composer and Git controls use already-available thread-shell metadata, eliminating a layout shift while preserving the existing detail-driven thread views. The affected fields and downstream behavior are straightforward to account for, with no schema, default, infrastructure, or sensitive-data changes.

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[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.6 KiB	13.6 KiB	−19 B (−0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.0 KiB	+1 B (+0.0%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.6 KiB	6.6 KiB	−20 B (−0.3%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	57.1 KiB	57.1 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.6 KiB	13.6 KiB	−29 B (−0.2%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.0 KiB	7.0 KiB	−3 B (−0.0%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.5 KiB	6.5 KiB	−26 B (−0.4%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.8 KiB	57.8 KiB	−44 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	9	8	−1 (−11.1%)	21	✅

Baseline: b5d8903 · PR result: 386cbef · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 113.9 KiB
• Claude decoded thread snapshot: 114.6 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Advanced

Run ID: 2a449b79-6a94-48f5-ad74-4abd76d8b0a1

📥 Commits

Reviewing files that changed from the base of the PR and between b5d8903 and 386cbef.

📒 Files selected for processing (3)

• apps/web/src/components/BranchToolbar.tsx
• apps/web/src/components/BranchToolbarBranchSelector.tsx
• apps/web/src/components/GitActionsControl.tsx

Included review availability: Your plan provides up to 10 included reviews per hour; 1 remains after this review.

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📝 Walkthrough

Walkthrough

Three web components now use useThreadShell for thread lookup. The changes remove draft-thread-dependent waitForShell options while preserving downstream server-thread consumers.

Changes

Thread shell lookup migration

Layer / File(s)	Summary
Update component thread lookups apps/web/src/components/BranchToolbar.tsx, apps/web/src/components/BranchToolbarBranchSelector.tsx, apps/web/src/components/GitActionsControl.tsx	The components import and call useThreadShell instead of useThread. Draft-thread-dependent waitForShell configuration is removed. Existing downstream consumers remain unchanged.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Merge Risk: ⚪ Minimal · up to 386cb

The composer context strip and git controls now read available thread-shell data rather than waiting for full thread details, preventing the reported layout shift. No concrete current-head merge-blocking risk remains.

Suggested reviewers: juliusmarminge, maria-rcks, extoci

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description explains what changed and why, but it does not follow the required template structure. It omits the UI Changes section and checklist, despite describing a visible UI change.	Add the required "## What Changed", "## Why", "## UI Changes", and "## Checklist" sections. Include before/after screenshots for the UI change and a short video if the interaction or layout shift requires motion evidence. Complete the check…
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 3 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the web layout-shift bug and the affected composer area. It is concise and related to the main change.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

Full details: Description check

Resolution

Add the required "## What Changed", "## Why", "## UI Changes", and "## Checklist" sections. Include before/after screenshots for the UI change and a short video if the interaction or layout shift requires motion evidence. Complete the checklist items or explain why any item does not apply.

• Fix all pre-merge checks with AI

✨ Finishing Touches 💡 1

📝 Generate docstrings 💡

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch t3code/fix-composer-bottom-bar-flicker

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