Latest update introduces a small UI bug when there is a scrollbar.
I also think this “filter” search box would be much more effective if it’s just a custom search query in the current category by default (instead of asking this if there is no result). The titles are very short, so in most cases there won’t be a hit to anything a non-familiar user would type there.
But you are losing the regular “forum” sidebar, so back to forum kinda makes sense here.