In a uiAccess=true process, a WS_EX_TOPMOST parent window causes
WebView2's internal cross-process SetParent to be rejected by UIPI,
returning E_INVALIDARG (0x80070057) from CreateCoreWebView2Controller.
This was triggered when the watchdog restarted the server while the IME
was already active: the floating toolbar showed early, which mistakenly
raised the DWM-cloaked (warmup) menu host to TOPMOST before its
controller existed. Manual launches never hit this because the IME was
inactive at startup time.
Changes:
- Gate RaiseTrayMenuAboveSmallWindows on menu controller existence so
a cloaked warmup host is never prematurely pinned TOPMOST.
- Strip WS_EX_TOPMOST from any host window before requesting its
controller; the lazy-topmost gate re-pins all three once ready.
- Serialize controller creation (one in-flight at a time) to avoid
E_INVALIDARG from concurrent CreateCoreWebView2Controller calls on
the same environment.
- Rotate past a persistently failing host so it cannot starve siblings.
- Harden LOCALAPPDATA resolution with SHGetKnownFolderPath fallback.
- Increase watchdog restart delay to 2s for user-data-folder lock drain.
- Add diagnostic logging (traymenu-diag.log) for WebView2 init states.
fanlusky