Hi,
I'm on Ubuntustudio 20.04 (XFCE, no compositing enabled) and basically all U-he VST3 plugins (e.g. Hive 11037) show a glitchy GUI with a "blinking" black rectangle on the bottom in Renoise 3.3.2 (most recent version):
When I move the window to the bottom and up again the GUI looks normal, but the rectangle is back when reopening it. VST2 is working fine and there are also no issues with Renoise 3.3.1 and Bitwig and Reaper.
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