I guess I might be the only person on the face of the planet dependent on PhotoGIMP so this might be useful for no-one but just on the offchance…

After updating Gimp to 3 and updating photogimp too, it was for me totally and utterly broken. I don’t know enough to say why, but it was. It loaded the new splash screen but when fully loaded the whole interface was the standard Gimp one and all interface tools, layouts etc were also (as far as I could tell) standard Gimp. I searched for answers but couldn’t find any. Maybe this is a ‘me’ issue or maybe the updates are too new or maybe photogimp doesn’t have enough of a userbase to notice.

So, I’ve ended up rolling back to gimp 2.10 and the 2020.1 version of photogimp. However, this is not a straightforward process. Here’s what I had to do (assuming flatpak).

Remove all photogimp bits and pieces from $HOME/.var, $HOME/.local and most especially $HOME/.config

DO NOT uninstall Gimp itself.

Then revert gimp 3.02 to 2.10 like so:

First you need the commit id of previous versions of Gimp.

flatpak remote-info --log flathub org.gimp.GIMP

For 2.10 its 83b335255cc239e223ada842f99107d1d6ce51b511a8ae2a278005c2e2809242

So this is technically an update even though we’re reverting not upgrading, so Gimp itself still needs to be installed. Might need to sudo the next command.

flatpak update --commit=83b335255cc239e223ada842f99107d1d6ce51b511a8ae2a278005c2e2809242 org.gimp.GIMP

Let it do its thing. When its ready, you can (optionally but I did) tell flatpak to ignore updates like so:

flatpak mask org.gimp.GIMP

When that’s all done, open and run gimp and you should now have 2.10

Close Gimp.

Now download photogimp 2022.1 from the releases page, then extract the relevant files into $HOME/.var and $HOME/.local respectively.

Double check $HOME/.config/GIMP is definitely gone.

Open Gimp again and you should have photogimp back to its pre-gimp3 self.