SwingSet2: focus being incorrectly transferred when LAF changed to Windows

Run SwingSet2 app., InternalFrame demo, select Frame0 frame (or any other), then select Frame4 frame. Notice that keyboard focus is actually on the Frame4 (up/down keys scroll frame contents, space key does nothing).

Now change LAF to Windows. Note, that the Frame4 frame is painted as focused, but actually focus is in InternalFrameGenerator frame on the first button (up/down keys do nothing, space key will create new window with the fish image, tab will transfer focus to the next button in this frame). In this situation the only way to transfer focus to Frame4 is to select another frame (not frame4) and only then select frame4. Clicking on the frame4 will not transfer focus to it.

This does not happens when changing to any other LAF (tried Metal, Motif and GTK).