Dany L

Hi, I meet the same behavior as @unfa described. I am on Ubuntu Studio 18.10 running Ardour 5.12.0 (the one included in the distro). QMidiArp is included in the distro and the lv2 plugins has the issue described. The QT UI does not display at all. Only the frame does display. https://i.imgur.com/6qlC0Kg.png If I run Ardour from the command line I see this message appears when opening the plugin. : QApplication: invalid style override passed, ignoring it. I tried running it with jalv.gtk as you suggested....