Here's the errors for Chrome that are repeated several times:
7/10/13 11:15:42.931 AM Google Chrome[652]: This exception was thrown inside thread: <NSThread: 0x78e89cb0>{name = (null), num = 1}. This thread is the main thread.
7/10/13 11:58:35.022 AM WindowServer[128]: CGXDisableUpdate: UI updates were forcibly disabled by application "Google Chrome" for over 1.00 seconds. Server has re-enabled them.
7/10/13 11:58:35.596 AM WindowServer[128]: reenable_update_for_connection: UI updates were finally reenabled by application "Google Chrome" after 1.58 seconds (server forcibly re-enabled them after 1.00 seconds)
Safari reports a similar error:
7/10/13 12:19:18.142 PM WindowServer[128]: CGXDisableUpdate: UI updates were forcibly disabled by application "Safari" for over 1.00 seconds. Server has re-enabled them.
7/10/13 12:19:18.986 PM WindowServer[128]: reenable_update_for_connection: UI updates were finally reenabled by application "Safari" after 1.85 seconds (server forcibly re-enabled them after 1.00 seconds)
Don't ask me what I did, but the problem has been fixed.