I get the same results as Rich with Ivan's appimage - plugins in $HOME/.config/GIMP/2.10/ work except gmic-qt. Ivan's also misses the apt-installed gmic unfortunately.
I looked inside Ivan's AppImage and its a brew of different techniques. He's brave attempting what he has done but it's probably not usable for a Gimp power user
My AppImage opens the apt-installed gmic 3.3.1 and even updates it. I don't have any installed Gimp on this box that I use for graphics.
I looked inside Ivan's AppImage and its a brew of different techniques. He's brave attempting what he has done but it's probably not usable for a Gimp power user

My AppImage opens the apt-installed gmic 3.3.1 and even updates it. I don't have any installed Gimp on this box that I use for graphics.