[PATCH v2 0/2] MR10889: ole32: Validate cached clipboard window handle in get_clipbrd_window.

[Aaron Yourk (＠ayourk)]

The OLE clipboard caches a per-process window handle. When the STA 
thread that created this window terminates, the window is destroyed 
but the stale handle remains cached. Subsequent OleSetClipboard 
calls use this stale handle, causing OpenClipboard to fail with 
CLIPBRD_E_CANT_OPEN.

Check whether the cached window is still valid using IsWindow() 
before returning it. If the window has been destroyed, clear the 
cache so a fresh window is created on the current thread. 

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=59519

--
  v2: ole32: Validate cached clipboard window handle in get_clipbrd_window.
      ole32/tests: Add test for OLE clipboard reuse across STA threads.
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10889