Comment by torstenvl

GTK4 is still pretty usable without libadwaita and all its Gnome-isms.

But frankly I think forking and maintaining GTK3 is preferable to moving to EFL or Qt. GIMP is still on GTK3. MATE is still on GTK3. Inkscape is still on GTK3 (but GTK4 work is in progress). Evolution is still on GTK3.

I think GTK3 will be around for a long time.