Yesterday, I have noticed interesting thing related to Finder and "beach ball of the death". Suddenly, for no obvious reason, the top menu became unavailable and cursor changed to beachball every time I moved it there. The Bluetooth mouse stopped responding. Finder stopped responding. All symptoms as if Finder would hanging ...
The cause of the issue was crash of unrelated application (iShowU, if you are curious), which brought up the crash report window. For some reason - maybe because it happened while changing spaces - the window was not visible. After closing the window, everything came back to life and even mouse reconnected (after disabling and re-enabling Bluetooth).
So next time it looks like an application did hang, make first sure that no windows expecting input are not open and hidden. Do not rely upon jumping dock icon - with bad luck and Spaces enabled, it is easy to switch the notification off.
Author Miro Adamy
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