System is Windows 11, PreSonus Studio One 6.5, BFD 3.4.5.28 VST plugin.
When I try to use one of the drop down menus, such as File, Tools, etc. the menu will drop down when I click on it, but none of the items in the menu will respond to me clicking, so I can’t load presets, drum maps etc.
It works perfectly in standalone mode.
Any idea what’s going on?
Yeah, same settings as you. It also doesn’t let routing, clear kit, no action works after Studio One 6.5 update. The issue is that I tried in Reaper and it works as usual. So we gotta report to Presonus too.
I Have the same problem with studio one 6.5 and BFD 3.4.5.28 VST plugin but with windows 10
BFD Player seems to work.
I also had this problem running Studio One on Windows 10. I am running BFD 3.4.5 build 28 gen.
I am happy to report upgrading to the latest version of Studio One (6.5.1.96553 Win x64 (Built on Oct 27 2023)) fixed the problem. 
Have exactly the same problem - but this extends to ALL drop-down menus - including trying to use the filters in the browser on the right hand side. It is SO annoying! Hopefully it will get fixed soon!
I’ll give that a try! Thanks!