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Changes between Version 5 and Version 6 of Ticket #15277, comment 12

v5	v6
6	6
7	7	If I hide file history but block redraw in the shell (session.update_loop.block_redraw()) then no crash unplugging display. Now my guess is that the screen removed callback is too late and a redraw happening before the screen remove is issued causes the crash. If I block for 100 seconds it still crashes. So it does seem that the crash happens before the remove screen callback is received.
	8
	9	Surprisingly logging the screen remove to a file shows that ChimeraX does get the screen remove callback before the crash. So why does it not crash if I block redraw before unplugging but it does crash if only the remove screen callback blocks redraw? It must be that a redraw occurs before the screen removed callback but it doesn't crash until later after the screen removed callback. In other words the crash is set up before the callback but happens after the callback.