Mac screen flashes when f13 pressed? I recently discovered that when I press f13 on my mac keyboard, the screen flashes white. It look exactly like when you take a screenshot except, it's not taking a screenshot. I have looked through all my keyboard shortcuts in settings, and can't find anything that is assigned to f13. I have tried to search online and I can't find anything on f13 assigned to anything on mac. I also have a hard time believing that this would be assigned to anything on mac by default because you have to have the extended keyboard to press f13.

NOTE: I am on a mac with yosemite.


EDIT: It also seems to occur when you press backspace in terminal when there is nothing left to delete

EDIT 2: I currently don't have the setting to flash on alert, so I don't know what it is.
Best guess would be …

System Prefs > Accessibility > Audio
You have "Flash the screen when an alert sound occurs" checked.

F13 has no default task - &amp; any invalid key pressed whilst in Finder will generate an alert [doesn't really do it in other apps, but does in Finder]