[BUG] Windows: Claude Code Desktop app shows sessions in sidebar but all message content missing after auto-update — content not persisted to claude-code-sessions JSONL files

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?

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

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Platform: Windows
App: Claude Code Desktop
Area: Session persistence / Desktop app

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What's Wrong?

After the Claude Code Desktop app auto-updated, all session message content
disappeared. The session list in the left sidebar still shows all previous
sessions correctly, but clicking any session shows "No messages yet." —
even for sessions that were actively used.

Reinstalling the app and clearing cache did not fix the issue.

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Steps to Reproduce

1. Use Claude Code Desktop on Windows over multiple sessions
2. App auto-updates in the background
3. Relaunch the app after the update
4. Session titles are visible in the left sidebar
5. Clicking any session shows "No messages yet." — content is gone

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Expected Behavior

All previous session message content should be visible after an app update.

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Actual Behavior

• Sidebar session list renders correctly (titles intact)
• All session message content is missing ("No messages yet.")
• Cache clear does not fix it
• Full uninstall + reinstall does not fix it
• Running /resume in the Claude Code CLI shows only a small subset

of sessions, confirming content was never flushed to the
claude-code-sessions JSONL files on disk

• The JSONL files in %APPDATA%\Claude\claude-code-sessions are all

only 1KB (empty stubs with no message content)

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Root Cause (suspected)

The Desktop app (Electron renderer) was storing session message content
in IndexedDB / in-memory cache but never properly flushing it to the
claude-code-sessions JSONL files on disk. When the update cleared the
Electron cache, all message content was permanently lost.

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Impact

Permanent data loss of all session conversation history prior to the update.
Work output files on disk are unaffected, but all conversation transcripts
are gone with no way to recover them.

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Additional Context

• %APPDATA%\Claude\claude-code-sessions contains JSONL files all sized 1KB
• %APPDATA%\Claude\DIPS-wal was 910KB at time of investigation (WAL not checkpointed)
• Claude Code CLI /resume only shows sessions from AFTER the update
• Issue persists across reinstall, confirming it is a data persistence

bug and not an Electron cache issue

What Should Happen?

NA

Error Messages/Logs

no error msg

Steps to Reproduce

NA

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

latest

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_