I would say it's not only an Xcode problem (but yeah, I have the same problem when I try to open the 'behavior' tab in preferences Xcode crashes on the external monitor. I've also noticed the same problem with the Wacom software. When I try to move 'Wacom Desktop Center' to an external monitor it also crashes with the same issue but when I use an external monitor as a main monitor application window can be displayed without any problem. It crashes only when I try to move windows from MBP built-in monitor to the external one (only one direction, the opposite works fine).
Anyway is there any update on this the issue persists for over a month already and I would say it's a major one.
a3nv
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