Is there such a site for multiple document editing by different users?

Question

CMS

There is a need for such a platform where people from one city could write, for example, an appeal. People do not know each other, they simply register on the site and edit the finished letter, adding, in their opinion, the necessary edits. Then the admin re-reads and adds or does not add. Something similar to Google Doc, only a separate one so that there would be a platform. Is there something similar?

Answer 1

Check out https://www.penflip.com

Answer 2

https://cryptpad.fr