>> - Tk 8.6 does what bootstrap does

>Which is?

Per TFA: "... when you try to move your mouse from the main menu to the submenu, the submenu will disappear out from under you like some sort of sick, unwinnable game of whack-a-mole."

http://static.tumblr.com/9hgswys/iU1mj8c6y/bootstrap-bug.gif