Check out Anytype it’s pretty much just an open source Notion, I like it a lot

It probably is using Synapse, the Beeper github links directly to the matrix ansible script which uses Synapse by default unless you change it

Thankfully I was not subscribed to that community so I wasn’t hit by it, but wow it’s a bad situation. I will certainly be more wary and keep an eye on things, ready to purge any images just in case