When I run editing tests on Mountain Lion, I sometimes encounter the following error: 2013-03-19 02:06:16.491 WebKitTestRunner[73413:707] In 'CFPasteboardCopyDataReturn __CFPasteboardCopyData(CFPasteboardRef, CFIndex, CFIndex, CFStringRef, Boolean)', file /SourceCache/CF/CF-744.12/AppServices.subproj/CFPasteboard.c, line 2373, during unlock, spin lock 0x112507018 has value 0x0, which is not locked. The memory has been smashed or the lock is being unlocked when not locked.