It'd be nice if Ctrl+I worked better even when that whole pane was hidden. Strangely it actually works fine, you just can't see it. Perhaps it should temporarily expand the pane, let you type in search terms and when you press enter, hide the pane again.
Sorry, it took me a couple of reads before I got what you meant.
I’ve changed the IDE so that the hidden pane pops out again if you type Control-I to focus the Action Types filter. Automatically hiding it again will have to stay on the Wish List for now, though. :).