Hi,
I think I'm seeing something similar right now. I'm using 3.389 on OSX 10.15.5. When I try to open the clipboard history via a trigger (as implemented via Simply: A modest touch bar preset) then I get a blank clipboard history, even though I definitely have been copying things while BTT is open. BTT is definitely open and running-- the Touch Bar portion works besides for the clipboard history. I also don't see the "disable clipboard manager" entry in the menu, which is shown in your screenshots here: How can I disable Clipboard/Pasteboard history for specific apps?
Am I missing something that I have to enable the clipboard manager? I've done a lot of googling and reading over all the documentation, and can't really see what I'm missing...
Thanks!