KWin, our fantastic and flexible window manager and Wayland compositor, can not just drive your session but also run in windowed mode for development purposes:
$ dbus-run-session kwin_wayland --exit-with-session kwriteEt voila, a windowed KWin appears, running KWrite. The separate DBus session is important so it doesn’t mess with your running session, notably trying to take over your global shortcuts.
You click a link in your chat app, your browser with a hundred tabs comes to the front and opens that page. How hard can it be? Well, you probably know by now that Wayland, unlike X, doesn’t let one application force its idiot wishes on everyone else. In order for an application to bring its window to the front, it needs to make use of the XDG Activation protocol.
You may have read about my new-found fondness for Plasma’s Clock app. Following the development of a “Picture in Picture” protocol for Wayland, I remembered how I once saw someone put up a little timer window during a lunch break while screen-sharing a presentation. I figured, I wanted that, too!
While I do have a Qt git build on my machine that I use for development, I usually only test individual applications and functionality but hardly ever run my full Plasma session on it. This means that for day-to-day use I typically only get to enjoy new Qt features once they have actually been released.
One of the key components to using a Plasma Wayland session is obviously the Qt Wayland Client module for running Qt applications in a Wayland environment. While it has been successfully deployed to millions of devices over the years, there’s still a few areas that feel like they haven’t been touched much since its inception as part of the Qt Lighthouse project, what turned into QPA, the Qt Platform Abstraction.
