on OS X Yosemite, minecraft causes black screen when disconnecting from servers

Same problem here. Needs a fix, my son just powers down the computer to fix it.

There is no way to exit the black screen from the mac, at least not that I could find. However, I can ssh from another computer to the imac. I can then kill the loginwindow process belonging to the minecraft user. Just killing the java and minecraftlauncher does not fix it.

Please force a crash by pressing F3 + C for 10 seconds while in-game and attach the crash report ([minecraft|http://hopper.minecraft.net/help/finding-minecraft-data-folder]/crash-reports/crash-<DATE>-client.txt) here.

See log attached. This is a crash where there is no black screen, instead the crash was forced using the method you suggested, F3+C for 10 seconds.

Does this occur if you remove the resource pack?

No idea. I'll ask my son to start testing, after removing the resource pack. I did do already a complete reinstall of yosemite and that did not help.

Ticket resolved as incomplete, because no answer in a reasonable amount of time (1+ year), if it still happens, please update the ticket.