Thank for correcting this imprecision of mine: indeed in the "Full Wayland" session, QT_QPA_PLATFORM seems to be kept to the value it is set to upstream, "wayland", and not as I wrote above, to "wayland;xcb". To summarize for anyone reading this: - GDK_BACKEND (Xwayland): set to xcb - QT_QPA_PLATFORM (Xwayland): set to xcb - GDK_BACKEND (Full Wayland): set to wayland - QT_QPA_PLATFORM (Full Wayland): set to wayland - GDK_BACKEND (upstream): unset - QT_QPA_PLATFORM (upstream): set to wayland I am arguing for doing things the way upstream does, which Fabian is willing to do but only if we get more user feedback. I'll be working with him off the list on the details of how to gather feedback in a way acceptable to him, but any suggestion or comment is welcome. Will update this thread when appropriate.