In-game window does not work properly when there are too many filters

[Kalmalyzer]

With more than a half-dozen filters, the in-game window will flicker between rendering at two different widths: The normal console width (which is about half a screen at 1920x1080), and a greater width which is determined by the total number of buttons. This is ugly.

With lots of filters, the scrollbar is no longer usable.