Need this uncountournable addon Rated 5 out of 5 stars

Just lake @Surfmlot My FirefoxDE updated and lost my goups that are amazingly useful to work in several work universes (different customers...).
Now I just have to try to downgrade Firefox and maybe I will have a chance to recover my groups... Maybe.
This is quite violent from mozilla to shutdown such features and screw all work from addons writers.