When I start the attached program everything seems to be fine at the beginning.
The program shows a tool bar and a drawing area with a lot of triangles.
The tool bar contains two toggle buttons. The first one toggles between
triangles and rectangles. If I hit this toggle button several times
(10 - 20 times on my machine) the visual state indication of the button
does not change anymore although the toggling itself still works.
Also the blue focus indication does not change anymore when I select
for example the first text box. When I finally change the window size
slightly everything goes back to normal.