Resize different FX windows?

Hello. I'm new to Reaper, but not to DAWs in general. I was wondering: Is there a way in Reaper to 'memorize' a certain sizing of the FX windows? Let me elaborate please. Reaper correctly expands the size of the window to fit the GUI (which it does perfectly) - but can it also shrink as well as you switch to a smaller FX? I can't seem to make it :( It's not Earth-shattering if it can't be done, I'm just curious if it can save me a few mouse clicks and constant resizing for screen real estate's sake. (Normally you'd likely start with Kontakt first, but for this example, to get a mental picture I went the other way). For example. I open a small Reverb plugin in an FX window - Reaper opens the GUI and fits it perfectly :) And now, say, I want to open Kontakt 4 in the same FX window - it expands perfect to fit the whole big Kontakt GUI. Awesome. But now, if I want to switch back to the reverb plug, it doesn't "resize" when going from large to small - only small to large. So, I end up with a huge screen of white space and a tiny reverb plug. I was just wondering if there is a way to have Reaper "follow" the size of a GUI, both ways - not just expanding from a smaller window -> large GUI. It does that perfect :) But when I go to a smaller plug, it remains at the large window until you resize it. It does not shrink to fit the smaller plug more tightly. But at least it always expands out again correctly when you use larger plugs though. Thanks for any feedback. Ben

In Preferences, under either Plugins or VST - I forget which - there are a pair of checkboxes telling Reaper whether to size the window up and/or down when you change effects.

In Preferences >> Plugins:

Score!!! That's awesome :) Thanks man, you rock! Such a clean, easy interface - so much easier and less tedious than other DAWs... Man I love Reaper - Ben