Etherpad 
Etherpad is a web-based collaboration platform that allows users to edit text documents together in real time. Multiple users can simultaneously access the same Etherpad document, make changes, and see what others are writing. Etherpad provides a simple and effective way for teamwork, brainstorming, collaborative writing, and more, without version conflicts.
Etherpad is also embedded in Jitsi Meet. This allows for shared notes to be captured during a meeting.
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My Offer
I've been running Etherpad since the end of 2020: pad.sp-codes.de