[CatOne]

Select them all, and then use the blindingly obvious shift-command-L shortcut.

Note on OS X if you go to "help" in-app and type something (i.e. flag) it will often point you to all the menu commands that do what you're looking to do. This is how I re-discovered the command because that shortcut, well, lots of the OF shortcuts are arcane key combinations, probably because there are so many of them ;-)