If in Customize mode, when clicking RMB on a toolbar and selecting to 'Factory Reset this Toolbar' the confirmation dialog appears behind the main Customize dialog... the lister is unresponsive while this dialog is open, making it confusing as to whats going on.
I know that you don't NEED to be in Customize mode to use this feature... but just the same, it's unintuitive behavior if you DO use the option while in Customize mode..