Humm, just realized that setting fullscreen is stated not to support even the windows in the same application, so no wonder it flashes back and forth when a Blocking dialog parented to the window is displayed. However it works perfectly in linux.
Very strange. I'm going to revert to the old strategy, but have you any clue why evt.getOppositeWindow() should return null in linux while the events refer to opening a application window? That seems like a real bug.
