Window corners don't render properly I have recently noticed that some of my windows have weird looking corners. It's like they are missing dark pixels right on the edge.



It doesn't always happen, some windows seem to be 'immune' - one example would be Messages, which is the window in the middle.

I'm running OS X 10.9.3.
After the OS X Mavericks v10.9.4 Update, window corners have returned to their previous glory. Update notes don't mention any issue of this kind, so I guess it might have been fixed as a side effect of running the system updater.

EDIT: Aaand the corners are ugly again. It's really weird.