Fullscreen windows with WS_EX_NOACTIVATE | WS_EX_TRANSPARENT interfere with GIMP UI events
Submitted by Michael Schumacher
Thanks to user Floatharr on #gimp, we figured out another application that interferes with certain features of the GIMP user interface on the Windows platform:
Strokes Plus http://www.strokesplus.com/
The software optionally uses an invisible window covering the whole screen to paint the gestures users make, and this interferes with the events GIMP (or GTK+) receives, it seems. We suspected similar behavior of the other applications doing this.