You can already try GIMP beta, only as appimage poorly (or ubuntu ppa, works through distrobox) and report bugs.
It is pretty good, needs better defaults and it is crazy how GTK3 was the one where stuff started to get HUGE.
So you see buttons etc are bigger, not fitting the menus anymore. But it works, and it finally has color profiles and nondestructive filters, which are a base requirement for graphics design.