They make collaboration software intended to be Google Cloud Office Suite alternatives.
https://degooglisons-internet.org/en/
I am not sure what to think of them, most things they make have bigger more popular open-source alternatives.
For instance they have Framadate which is pretty cool, and way more usable than the hell Doodle has become.
And even if most of their software isn't unique, it's beneficial to have a bunch of it from the same open source collective with the same guarantees (you can be pretty sure they won't switch to a BSL or similarly restrictive license).