[BUG] Cowork UI shows zero projects/conversations after macOS major update + logout, while all local data files remain intact on disk

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Environment

• Claude Desktop: 1.8555.2
• macOS: 26.5 (Tahoe) — issue appeared right after updating from 26.2 → 26.5
• No VPN, correct account logged in

Summary

After a macOS major version update, the Cowork interface became completely empty (zero projects, zero conversations, zero scheduled tasks). All underlying data files are still present on disk — this is a UI catalog / local index problem, not data loss.

What's intact on disk

• ~/Documents/Claude/Projects/ (ateliers-cowork, Bootcamp cowork, …)
• ~/Documents/Claude/Scheduled/ (scheduled tasks)
• ~/Documents/Claude/Artifacts/
• ~/Desktop/cowork/ (deliverables)
• ~/Library/Application Support/Claude/Partitions/cowork-artifact-…
• ~/Library/Application Support/Claude/claude-code-sessions/ and local-agent-mode-sessions/

Steps taken (per support guidance)

1. Full app restart → no effect. Notably, app does NOT rewrite IndexedDB/app_localhost_0.indexeddb.leveldb on launch (frozen at 20 KB since Apr 29).
2. Logout / login → made it WORSE: logout purged IndexedDB/https_claude.ai_0.indexeddb.leveldb (488 KB → 12 KB) and cleared the LSS-persisted.starred-cowork-spaces / cowork-read-state keys in Local Storage (which previously referenced my spaces, e.g. "bootcamp"). After re-login, UI still empty. bridge-state.json unchanged before/after (same session 6fa82dc4-…:1bc9c729-…) → not an account/org switch.
3. Restored pre-logout IndexedDB/https_claude.ai (388 KB) with app fully closed → app keeps it and grows it, but UI does not display the content.
4. Restored pre-logout IndexedDB + Local Storage together, app fully closed → UI still empty.

Diagnosis / open question

The Cowork UI catalog (list of spaces & conversations) is apparently not rebuilt from IndexedDB/https_claude.ai, Local Storage, bridge-state.json, nor from the on-disk Partitions/sessions. Where is the UI catalog stored, and is there a way to rebuild it from the still-present local partition/session files?

Notes

• Cowork has no cloud sync, so the catalog is local-only — and logout purged it.
• I have full backups of the pre-logout state (IndexedDB + Local Storage + Partitions + sessions) and can share specific files or run diagnostic commands on request.

Technical identifiers

• environmentId: env_01VGpWzShBRR8chCNBqR9mdW
• remoteSessionId: cse_01Fvy9c9B9Hu7gjThcpJTa9b
• session key: 6fa82dc4-cd2d-4b83-9581-de543775489c:1bc9c729-a5d6-4f64-b4f2-d23f52367993

What Should Happen?

On launching Claude Desktop, the Cowork interface should display my existing spaces, projects, conversations and scheduled tasks — the same ones whose data files are still present on disk (in ~/Documents/Claude/ and ~/Library/Application Support/Claude/Partitions). After the macOS update (and after a logout/login), the UI catalog should be rebuilt from the local data rather than showing an empty state.

Error Messages/Logs

No visible error message in the UI — it simply shows an empty state.

Relevant observation from IndexedDB LevelDB LOG after logout:
- `IndexedDB/https_claude.ai_0.indexeddb.leveldb` dropped from 488 KB to 12 KB (new MANIFEST), i.e. the store was wiped on logout.
- `Local Storage` keys `LSS-persisted.starred-cowork-spaces` and `cowork-read-state` no longer reference my spaces (they did before logout, e.g. "bootcamp").

Steps to Reproduce

1. Use Claude Desktop with several Cowork spaces/projects and conversations (stored locally; Cowork has no cloud sync).
2. Update macOS across a major version (in my case 26.2 → 26.5).
3. Relaunch Claude Desktop → the Cowork interface is completely empty (0 projects, 0 conversations, 0 scheduled tasks), even though all data files are still on disk.
4. Attempted recovery (none restored the UI):

a. Full app restart → no effect.
b. Logout / login → made it worse: logout purged IndexedDB/https_claude.ai_0.indexeddb.leveldb (488 KB → 12 KB) and cleared the starred-cowork-spaces / cowork-read-state keys in Local Storage. UI still empty after re-login. bridge-state.json unchanged (same session) → not an account/org switch.
c. Restored the pre-logout IndexedDB file (388 KB) with the app fully closed → app keeps and grows it, but UI does not display the content.
d. Restored IndexedDB + Local Storage together with the app fully closed → UI still empty.

Note: the Cowork UI catalog appears NOT to be rebuilt from IndexedDB, Local Storage, bridge-state.json, nor the on-disk Partitions/sessions.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Worked normally before the macOS 26.2 → 26.5 update (Claude Desktop was functioning on macOS 26.2). I don't have the exact prior app build number.

Claude Code Version

Claude Desktop 1.8555.2

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• I have full local backups of the pre-logout state (IndexedDB + Local Storage + Partitions + sessions) and can share specific files or run diagnostic commands on request.
• All Cowork working data is still present on disk: ~/Documents/Claude/{Projects,Scheduled,Artifacts}/, ~/Desktop/cowork/, and ~/Library/Application Support/Claude/Partitions/cowork-artifact-…
• Technical identifiers: environmentId env_01VGpWzShBRR8chCNBqR9mdW · remoteSessionId cse_01Fvy9c9B9Hu7gjThcpJTa9b
• This was confirmed by Anthropic support as having no documented procedure to rebuild the Cowork UI catalog from local files; they recommended filing this issue.