Well, if we should be getting XP_EVENT_WINDOW_STATE_CHANGED on expose window changes, we're not. I just verified it with DEBUG_LOG, and the only time I'm ever seeing XP_EVENT_WINDOW_STATE_CHANGED is on show/ hide (including spaces "F8")... plus it seems like that is how it should be, right? If X11 is the foreground applicaiton, Expose works for selection the first window made by X11. If you select any other X11 window, hit F9, then choose the first X11 window, focus switches correctly. Doing this shows the following in the debug log: quartz.c:QuartzProcessEvent:501 kXDarwinBringAllToFront darwinEvents.c:ProcessInputEvents:535 kxDarwinUpdateModifiers(0, 0, (empty)) when you try focusing on another window via expose, focus remains on the current window, and you just see: darwinEvents.c:ProcessInputEvents:535 kxDarwinUpdateModifiers(0, 0, (empty)) FTR, I'm almost positive that the kXDarwinBringAllToFront is a biproduct of it working, not the cause of it working. Additionally, QuartzProcessEvent isn't getting the kXDarwinActivate event when switching in from another application via expose like it is when switching normally.