GIMP plugins are great but a bit hacky to install. Even for famous plugins such as Resynthesizer (which contains the super useful heal selection tool), the documentation recommends to download and copy-paste Python files into the installation directory.
I installed GIMP as a Flatpak through the Software Center on Ubuntu. I had a pleasant surprise: a selection of plugins is available for one-click install. This functionality was mentionned nowhere in the documentation, since it came out in a recent release.
So far, the list includes:
BIMP
FocusBlur
Fourier
BimpLensFun
G’MIC
LiquidRescale
Resynthesizer
Thanks to the Flatpak team who made this possible!