[Windows] Store Codex 26.924.2738.0 spinner / blank UI on Intel UHD 630; DComp + SwiftShader do not fix; logs healthy #48748

Summary
Windows Store Codex Desktop opens a window but the client area never paints — only a spinner. Auth, React render, and WebSocket/pubsub all succeed in logs. --disable-direct-composition (and SwiftShader / disable-gpu) do not restore painting on Intel UHD Graphics 630.

Environment
App: OpenAI.Codex_26.924.2738.0_x64__2p2nqsd0c76g0 (Microsoft Store / MSIX)
OS: Windows 11 Pro 10.0.22631 (x64)
GPU: Intel(R) UHD Graphics 630, driver 31.0.101.2135
Related: #40878 (DComp workaround does not fix this machine)
What we tried
Confirmed %USERPROFILE%.codex\config.toml has no approval_policy = "untrusted".
Clean Microsoft Store reinstall of build 26.924.2738.0 — same spinner.
Reset Electron web profile (...\Roaming\Codex\web renamed aside).
Launched via IApplicationActivationManager.ActivateApplication with package identity + flags: --disable-direct-composition --disable-gpu --disable-gpu-compositing --use-angle=swiftshader --use-gl=angle (Verified on main ChatGPT.exe command line.)
Network OK: TCP 443 to chatgpt.com / auth.openai.com; logs show chatgpt_pubsub_transport_opened.
Observed process / window
Main window exists (non-zero MainWindowHandle, title ChatGPT, on-screen).
Child processes (GPU/network/renderer) healthy; UI still spinner-only.
Sanitized log excerpts (Windows app logs)
Log file (name only): codex-desktop-d4d0334d-6261-4b9b-8610-845a0df507ae-20568-t0-i1-164017-0.log
Path pattern: %LOCALAPPDATA%\Packages\OpenAI.Codex_*\LocalCache\Local\Codex\Logs\

2026-09-27T16:40:17.695Z info [sparkle] in_app_updates_policy_wait_started timeoutMs=300000
2026-09-27T16:40:17.924Z info Launching app agentRunId=null allowDebugMenu=false allowDevtools=false allowInspectElement=false buildFlavor=prod enableSparkle=false enableUpdater=true nodeEnv=undefined packaged=true platform=win32
2026-09-27T16:40:18.001Z warning Failed to start the Artifact Session host errorMessage="Artifact Session host Unix-socket transport is not available on Windows."
2026-09-27T16:40:19.320Z info [window-manager] window ready-to-show appearance=primary hostId=local startupElapsedMs=1251 webContentsId=1 windowId=1
2026-09-27T16:40:20.767Z info [electron-message-handler] [statsig-refresh-diagnostics] React root render requested rendererWebContentsId=1 rendererWindowAppearance=primary rendererWindowFocused=true rendererWindowId=1 rendererWindowVisible=true windowType=electron
2026-09-27T16:40:21.873Z info [electron-message-handler] [chatgpt-account-lookup] completed authenticatedAccountPresent=true authMethod=chatgpt result=succeeded
2026-09-27T16:40:26.005Z info [electron-message-handler] chatgpt_pubsub_transport_opened rendererWebContentsId=1 topicCount=1
2026-09-27T16:40:26.054Z info [electron-message-handler] chatgpt_pubsub_topic_subscribed topicId=resource-updates
2026-09-27T16:42:20.490Z info [electron-message-handler] client.performance.span name=app_start outcome=failure reason=timeout durationMs=122329.6 initialSurface=home
2026-09-27T16:45:17.700Z info [sparkle] in_app_updates_policy_timeout policy=pending timeoutMs=300000

Notes
OpenAI support: no service incident; no end-user Store rollback path.
Interim clients: https://chatgpt.com/codex and Codex CLI 0.157.1 (codex doctor OK).
Happy to attach fuller sanitized logs if needed. Session transcripts under %USERPROFILE%.codex\sessions not attached (may contain chat content).