Do not allow offscreen widgets to take grabs.
Submitted by Robert Carr
Created attachment 195989 Patch
In gtk_grab_add and gtk_device_grab_add, it makes sense to check if the widget is offscreen before allowing it to make a grab.
- We don't want offscreen widgets closing menus, etc...
- If the widget is put in an offscreen hierarchy it probably indicates that the user wants greater control over the widget.
Patch 195989, "Patch":