[BUG] [macOS M1 Pro] Artifacts tab in sidebar never syncs - always empty despite successful publish

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?

Artifacts published in Claude Desktop do not appear in the "Artifacts" sidebar tab,
even though they publish successfully and appear correctly in claude.ai/artifacts
when accessed through the web browser.

This is a synchronization issue between the Desktop client and the backend -
the backend works correctly, but the local Desktop sidebar fails to render published artifacts.

What Should Happen?

After publishing an artifact, it should appear immediately (or within seconds)
in the "Artifacts" sidebar tab on Claude Desktop, synchronized with the published
state on the server.

Error Messages/Logs

The "Artifacts" sidebar tab displays no artifacts regardless of how many have been 
published. The tab exists and is clickable, but the content area remains empty.

Steps to Reproduce

1. Open Claude Desktop
2. Create an artifact in a conversation (e.g., simple HTML page)
3. Click the "Publish" button on the artifact
4. Wait for confirmation that artifact published
5. Check the "Artifacts" tab in the left sidebar
6. Expected: Artifact appears in the sidebar list
7. Actual: Artifacts tab remains completely empty

Claude Model

Not sure / Multiple models

Is this a regression?

No, this never worked

Last Working Version

N/A - Never worked in Desktop

Claude Code Version

Claude Desktop 1.21459.3 (not Claude Code - this is a Desktop app bug)

Platform

Other

Operating System

macOS

Terminal/Shell

Other

Additional Information

Environment

• Application: Claude Desktop
• Version: Claude 1.21459.3 (e0f338)
• OS: macOS Tahoe 26.5.2
• Hardware: MacBook Pro M1 Pro
• Feature Status: "Code execution and file creation" enabled in Settings > Capabilities

Additional Verification

• Log into claude.ai/artifacts in a web browser with the same account
• The published artifacts appear correctly in the web interface
• Conclusion: The backend and publishing mechanism work fine; the issue is Desktop-specific

Troubleshooting Already Completed

The following steps were attempted without resolving the issue:

• ✅ Restarted Claude Desktop (Cmd+Q)
• ✅ Cleared app cache
• ✅ Deleted ~/Library/Caches/Claude
• ✅ Cleared ~/Library/Application Support/Claude
• ✅ Completely uninstalled and reinstalled Claude Desktop
• ✅ Logged out and back in
• ✅ Full Mac restart
• ✅ Created new artifacts in fresh conversations
• ✅ Confirmed running latest version from claude.com/download

Impact

• Creates user confusion (appears broken even though it technically works)
• Generates anxiety about app reliability
• Forces users to use web interface instead of Desktop
• Blocks decision to purchase paid plan (user doesn't trust the Desktop app)

Additional Context

• The problem occurs 100% consistently
• Affects all artifact types (HTML, React, SVG, Markdown)
• Only affects Desktop; web interface works perfectly
• No errors are shown in the UI
• This appears to be a client-side rendering or state synchronization bug
• I am using the latest version of Claude Desktop (1.21459.3)
• Platform: macOS (Claude Desktop app, not Claude Code CLI)

Support Reference

Previous support conversation ID: 2154751111135657

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<img width="1565" height="994" alt="Image" src="https://github.com/user-attachments/assets/6cf96877-4424-4b32-a6dd-646e226af09d" />