To reproduce: 1. Download the attached file to LayoutTests/platform/win/plugins 2. run-webkit-tests -p --reset-results plaform/win/plugins/overflow-clip.html 3. Open LayoutTests/platform/win/platform/win/plugins/overflow-clip-expected.png The (quite colorful) plugin is overlapping the text. It should be clipped to a 50x50 square. The clipping works fine in the browser, and in DRT (if you modify DRT to put its window on screen). But when creating the image for the pixel dump via WM_PRINT, the plugin's clip seems to be ignored by Windows. It would be good to have a way to make pixel tests of clipped plugins.
Created attachment 72999 [details] test case
<rdar://problem/8633402>
We clip plugins using ::SetWindowRgn. I guess WM_PRINT doesn't pay attention to the window's window region. :-\
This affects how plugins appear in Safari's dragged-out tab mini-windows, too.
Webkit / Safari does not support plugins anymore so I think we can close this. Marking this as "RESOLVED WONTFIX". Please reopen, if it is still needed. Thanks!