Chats/Projects sidebar section disappears after updating to 2.2553.1 (Windows)

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### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) 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?

Description:

After the desktop app auto-updated to version 2.2553.1 on 2026-09-18, the entire "Chats and Projects" section vanished from the left sidebar on that device. Only the "Code" tab remains visible (New / Artifacts / Routines / Customize), showing an empty session list. All previously pinned Projects and chat history became completely inaccessible from the UI — not archived, not hidden behind a collapsed section, just gone from navigation entirely.

Comparison with a second device (same account, not yet updated):
A second computer signed into the same account, still running the pre-2.2553.1 version (shows a "Relaunch to update v2.2553.1" banner, not yet applied), displays the normal full interface: New / Projects / Artifacts / Scheduled / Customize / More, with pinned Projects and a complete, correct chat/task history list spanning weeks. This strongly suggests the issue is a client-side regression introduced in 2.2553.1, not server-side data loss — the account's actual data is intact and reachable from a device on the older version.

Steps to reproduce (as far as I can tell):

Have an account with existing Projects/chat history.
Let the app auto-update to 2.2553.1.
Observe: the Chats/Projects sidebar section is gone; only Code tab remains.

Environment:

OS: Windows 11 Home Single Language, build 10.0.26200
App version: 2.2553.1 (updated from an earlier version on 2026-09-18)
A second device on this account remains on the pre-update version and is unaffected

Troubleshooting already tried on the affected device (no effect):

Log out / log back in
Full computer restart

Note: Have not yet uninstalled/reinstalled, holding off since that generates a new local device ID and might complicate diagnosis — happy to try if a maintainer suggests it's safe/useful.

### What Should Happen?

After updating to app version 2.2553.1, the "Chats and Projects" section should still appear in the left sidebar, and all previously existing Projects (e.g. a pinned "Venus企服公司" project) and chat history should remain visible and accessible — the same as they are on another device signed into the same account that has not yet updated to this version.

### Error Messages/Logs

No error/crash — this is a UI navigation issue (missing sidebar section), not a script error.

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### Steps to Reproduce

1. On a device where the account has existing Projects/chat history, let the Claude desktop app auto-update to version 2.2553.1.
2. Open the app after the update.
3. Observe: the "Chats and Projects" section is missing from the left sidebar entirely. Only the "Code" tab remains, with an empty session list.
4. Compare with a second device on the same account that has not yet updated (still on the pre-2.2553.1 version) — that device shows the full sidebar (Projects/Artifacts/Scheduled/Customize) with all Projects and chat history intact.

### Claude Model

None

### Is this a regression?

Yes, this worked in a previous version

### Last Working Version

pre-2.2553.1

### Claude Code Version

1.0.123 (Claude Code)

### Platform

Anthropic API

### Operating System

Windows

### Terminal/Shell

Other

### Additional Information

_No response_

No source files or tests are named. First reproduce the missing sidebar on Windows 11 with Claude Code 2.2553.1, then compare it with the pre-2.2553.1 behavior on the second device. Done means the Chats and Projects section, pinned Projects, and chat history are visible and accessible after updating.

Written by the indexing model from the issue text.