Fedora is pretty aggressive with updating KDE. They push major new versions during a Fedora release.

HDR is new ground on Linux, so it’s understandable it’s taking a while. It requires involvement from all over the graphics stack: graphics drivers, mesa, Wayland protocol, protocol needs to be implemented in compositor, apps need to implement the protocol.

You can right now. If you are using KDE, it should work with mpv, though you might need to launch it from terminal with a few flags to tell mpv to use HDR.

If you’re not using KDE, you can launch gamescope with the hdr flag in the tty and have it launch mpv.

Though I’m not sure any browsers have working HDR. I think Chromium may have some stuff in progress. Gnome Web may get it since WebKit supports HDR and HDR is being worked on for GTK.

They as in Wayland? Xorg doesn’t have HDR either and never will.

I would like to remind everyone that while this extension does not include display response measuring and calibration, they will come later.

No calibration yet.

This is the protocol for HDR content. KDE already ships an experimental version of it.

True, although not in the same way. KDE is using its own GTK theme and uses ~/.config/gtk-3.0/gtk.css to override colors to the accent color. But this method is broken for sandboxed versions of Firefox since they can’t access ~/.config/gtk-3.0/gtk.css (though with flatpak you could create an override to allow it).

I believe (and hope) Firefox is now following the standardized accent color portal for determining the accent color. If so, then this accent color change should work on Gnome, KDE, Pantheon, and other desktops that support the accent color portal. If true, then even sandboxed apps should follow the accent color without messing with the sandbox.