Phoronix Reader: "GTK3 Kills Support For KDE"

It was the subject line of a news tip this weekend...

A (older) GNOME bug report was pointed out to us in regards to the KDE experience now being degraded by GTK with the common oxygen-gtk theme breaking under modern versions of GNOME's tool-kit. The oxygen-gtk theme is used by several distributions while running GTK applications under KDE in order to provide a better and more matching experience by being a port of the default KDE widget theme to GTK.

Hugo Pereira Da Costa, the developer that's been porting the Oxygen widget style to GTK3 the past few years, expressed his frustration in the aforementioned bug report that GTK's theming engine has been effectively deprecated as of GTK+ 3.14 and is ignored for rendering. For supporting the latest versions of GTK+, this would require oxygen-gtk be written to use CSS styling rather than the GtkThemingEngine, which would lead to a lot of new work and the current port tossed out. In other words, oxygen-gtk is broken on the latest versions of the GTK tool-kit.

However, GNOME/GTK developers are unlikely to restore the support given the comments in the thread. GTK developer Ben Otte also commented, "As for oxygen-gtk in particular, I'm actually happy that it's stopped working because its codebase has been explicitly violating the contract for theming engines since its inception."

That was all several months ago. However, that bug report is now back to being active with developers/users disagreeing over the removal of this functionality. One KDE user commented this weekend, "I implore you to undepreciate this part of Gtk 3. If you would like to remove support for it, this is clearly something to do for Gtk 4. You *have* broken compatibility and the promise between minor versions. Even though the API still compiles, it essentially does nothing now. Hence, this is a Gtk 3 *regression*."

GNOME developers have confirmed though that it's too late and since the original bug report -- with all of the GTK+ 3.16 development having passed and GTK+ 3.17 releases going on -- this work on removing theming engines has resulted in lots of code refactoring and new feature additions that are now possible, but that makes restoring the theming engine support out of the question.

There are no plans to port oxygen-gtk to CSS, at least by its current developer, so its future currently looks rather bleak.