I would like to avoid gtk
In general everything should be based on Qt5. For now there are two apps pulling in gtk: NetworkManager applet and Anaconda. For the NetworkManager applet I hope I can fork the Plasma one and modify the parts using the plasma stuff to use normal systray instead.
As for NetworkManager there's already a panel applet nm-tray developed by an LXQt team member.
It's relying on NetworkManagerQt making it a Qt-only application. Unfortunately it's still in its alpha stages and there's even no upstream release so far. Yet I wonder whether supporting this project may be the better approach than starting a fork of the KDE stuff from scratch.
Did not know that project right now, thanks! Looks quite similar to my idea, except… it already exists :)
On a more general note I doubt a reasonable GTK-free desktop system is already feasible right now.
There are just too many important GTK applications without Qt counterpart, e. g. Gimp or Inkscape. Also, xscreensaver-demo is a GTK application that's included by now and not that easy to replace.
So besides I'd personally love to get rid of GTK rather sooner than later for a number of reasons I guess not too much effort should be put in that attempt atm as it won't succeed anyway.
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