Hi @Vinod Kumar, Thanks for your reply. The second screen is connected via a USB-C docking station (//store.hp.com/us/en/pdp/hp-usb-c-universal-dock), it doesn't look like it has its own graphics card, but I'm not sure.
Enpass does not work on a second screen attached to my notebook, neither started directly on the second screen (there the window keeps completely white) nor after succesfully starting on the primary screen and then moving the app window to the second screen (there the app does not get any keyboard or mouse events). After moving the runnig app window to the primary display again, it works fine again. Is this a bug or a security feature I didn't know of?