Claude Desktop (Windows, packaged/MSIX): "Launch at login" toggle does not persist

Product: Claude Desktop for Windows, packaged install (Claude_1.24012.9.0_x64__pzs8sxrjxfjjc)

Steps to reproduce:

1. Open Settings → enable "Launch Claude at login" (auto-start)
2. Close Settings
3. Reopen Settings → toggle shows OFF again

Technical findings:

• The HKCU\Software\Microsoft\Windows\CurrentVersion\Run\Claude value (pointing directly at the versioned app\Claude.exe path) disappears shortly after being set — enabling the toggle does not leave a persistent registration.
• The AppX manifest declares a windows.startupTask extension (TaskId="ClaudeStartup", default Enabled="false"), but no corresponding StartupApproved\StartupList entry is ever created, suggesting the app isn't actually using the packaged StartupTask API and instead writes/removes a plain Run key that doesn't stick.
• Workaround: manually registering HKCU\...\Run\Claude = explorer.exe shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude restores auto-start reliably (version-independent, survives app updates).

Expected behavior: the toggle should remain ON and Claude should launch automatically at Windows sign-in.