This was fixed in some older version, but apparently I ran into this again:
There seems to be (still, again?) something wrong with the keyboard forwarding to VST plugins. I tried with Repro 1 (VST3) and Vitalium (VST3) and Hive (VST2). It should work when the VST window is not focused which basically works, but sometimes notes played on the computer keyboard don’t trigger notes in the plugin and I can’t switch between e.g. mixer and editor view. So connection get’s somehow lost. With midi keyboard it’s fine and always working.
Looks like that the focus is stuck to the plugin (as seen from the color of the window boarder). Closing and reloading the GUI fixes it, but it’s getting lost again after a while.
This behaviour can be triggered by holding down a key with the PC keyboard while moving a slider on the VST synth with the mouse (=both, Renoise and the VST seem to be focused).
Switching off “Overwrite window mangaer shortcuts” fixes it, but is not a solution.
link to the beta tester section: https://forum.renoise.com/t/fixed-rc2-linux-xfce-vst-plugin-guis-sometimes-break-keyboard-input-note-playback-in-renoise/66558