KF5/Qt5 and multiple QPAs

[René J.V. Bertin]

Hi,

Am I correct that Qt now provides a Wayland QPA and that users on Linux can now decide, in principle "on the fly" which displaying protocol a newly started application is going to use, presumably with a platform-wide default either hardwired into Qt or defined in some settings file?

If so, how does that work out with KF5 applications that get started by others? Say, a user with a Wayland-based desktop logs in over ssh+X11 and wants to run kate remotely with `kate -platform xcb`. A new session dbus will be started, and during Kate's start-up sequence kdeinit5 will start which will then start klauncher.

I just tried this on OS X (I have a working XCB QPA on my system, plus a patched dbus that works without launchd). kdeinit5 starts up fine because it's not a GUI app (I think), but klauncher is. It doesn't inherit the `-platform xcb` arguments, and thus fails because the Cocoa QPA only works locally.

Mostly asking out of curiosity, though I would of course appreciate it if on occasion I could use applications like Kate remotely.

Thanks,
René