[Osvaldo Ortega (osortega)]

Summary

Keep the sandbox chat input visible and editable while cached or recorded history is displayed and the live connection is loading. Previously, the history model's read-only flag could hide the composer between history loading and live attachment.

Reuse the existing input-blocked state until live content is ready, without changing the history model or adding configuration. Sending remains disabled. Preserve archived-chat restrictions and recovery actions, and retain the Editor Window's existing connection-on-open policy.

No linked issue was provided.

Validation

The initial change passed client transpilation, 187 targeted browser tests, changed-file ESLint, and the patch whitespace check after rebasing onto main. The review follow-up also passed the ChatWidget suite (131 passing, 4 existing skips) and changed-file ESLint. Both reported bugs were reproduced by regression tests before applying the fixes.

Exact commands and results

Client transpilation — passed:

npm run build-fast -- --client-only

Targeted browser tests — 187 passed:

npm run test-browser-no-install -- --browser chromium --reporter dot \
  --run src/vs/workbench/contrib/chat/test/browser/remoteAgentHost/cloudSandboxSessionHandler.test.ts \
  --run src/vs/sessions/contrib/chat/test/browser/chatView.test.ts \
  --run src/vs/sessions/contrib/providers/remoteAgentHost/test/browser/cloudSandboxAgentHostContribution.test.ts \
  --run src/vs/workbench/contrib/chat/test/browser/remoteAgentHost/editorCloudSandboxContribution.test.ts \
  --run src/vs/workbench/contrib/chat/test/browser/widget/chatWidget.test.ts \
  --run src/vs/workbench/contrib/chat/test/common/chatService/chatService.test.ts \
  --grep 'CloudSandboxSessionHandler|Sessions - Chat View|keeps the sandbox composer|history recovery remains visible|policy read-only banner|renders history during automatic resume|opens original offline history|blocks submission without accepting input|passes read-only transitions|a visible read-only composer refuses|blocked input rejects send'

Changed-file ESLint — passed:

npm run eslint -- \
  src/vs/sessions/contrib/chat/browser/chatView.ts \
  src/vs/sessions/contrib/chat/test/browser/chatView.test.ts \
  src/vs/workbench/contrib/chat/browser/remoteAgentHost/cloudSandboxSessionHandler.ts \
  src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts \
  src/vs/workbench/contrib/chat/test/browser/remoteAgentHost/cloudSandboxSessionHandler.test.ts \
  src/vs/workbench/contrib/chat/test/browser/remoteAgentHost/editorCloudSandboxContribution.test.ts \
  src/vs/sessions/contrib/providers/remoteAgentHost/test/browser/cloudSandboxAgentHostContribution.test.ts \
  src/vs/workbench/contrib/chat/test/browser/widget/chatWidget.test.ts

Review-fix ChatWidget tests — 131 passed, 4 skipped:

npm run test-browser-no-install -- --browser chromium --reporter dot \
  --run src/vs/workbench/contrib/chat/test/browser/widget/chatWidget.test.ts \
  --grep 'ChatWidget'

Review-fix ESLint — passed:

npm run eslint -- \
  src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts \
  src/vs/workbench/contrib/chat/test/browser/widget/chatWidget.test.ts

Patch whitespace — passed:

git --no-pager diff --check origin/main...HEAD

Manual verification

Not performed against a live sandbox. To verify:

1. In the Agents Window, open an existing disconnected sandbox conversation and begin composing while it connects.
2. Confirm the input, draft, focus, and selection survive recorded-history loading and live attachment; sending stays disabled until live content is ready.
3. Confirm archived/read-only chats still hide the input and history failures retain their recovery actions.
4. In the Editor Window, confirm opening offline history allows drafting without automatically waking the sandbox.

[Copilot]

🟡 Changes recommended

Recovery-banner layout and archived subagent composer handling still need correction.

2 open issues

• Relayout transcript when recovery banner visibility changes · New
• Hide composer for offline subagents in archived sandboxes · New

What changed in this PR

Keeps sandbox chat drafts editable while recorded history is displayed and live content is loading, without enabling sending.

Changes:

• Keeps recorded sessions input-blocked until live content is ready.
• Updates composer visibility, archive handling, and recovery banners.
• Adds regression coverage and documents offline drafting.

File	Description
src/​vs/​workbench/​contrib/​chat/​test/​browser/​widget/​chatWidget.test.ts	Tests composer visibility and recovery actions.
src/​vs/​workbench/​contrib/​chat/​test/​browser/​remoteAgentHost/​editorCloudSandboxContribution.test.ts	Checks offline drafting without waking compute.
src/​vs/​workbench/​contrib/​chat/​test/​browser/​remoteAgentHost/​cloudSandboxSessionHandler.test.ts	Tests blocking through live attachment.
src/​vs/​workbench/​contrib/​chat/​browser/​widget/​chatWidget.ts	Adjusts archive and recovery-banner visibility.
src/​vs/​workbench/​contrib/​chat/​browser/​remoteAgentHost/​cloudSandboxSessionHandler.ts	Blocks input until live content attaches.
src/​vs/​sessions/​contrib/​providers/​remoteAgentHost/​test/​browser/​cloudSandboxAgentHostContribution.test.ts	Checks blocking during automatic connection.
src/​vs/​sessions/​contrib/​providers/​remoteAgentHost/​REMOTE_AGENT_HOST_SESSIONS_PROVIDER.md	Documents Editor Window offline drafting.
src/​vs/​sessions/​contrib/​chat/​test/​browser/​chatView.test.ts	Covers recorded-history composer transitions.
src/​vs/​sessions/​contrib/​chat/​browser/​chatView.ts	Keeps blocked composers visible with recorded history.

_{Review effort: Balanced}