How do I remove posts?

That and editing.. I wonder too.

It seems editing only works when you're in "Home" or 'private" mode.
As those posts are not written to the blockchain, they can be edited.
I guess the other posts are "public" and written to the blockchain and therefor can not be edited and it seems also not deleted.
Not sure.

you can archive your messages or replies inside your thread even from other users https://home.treechat.ai/quest/db9d0a38-09f3-4a02-8ef2-04eb7289f3f7

Interesting feature. I didn't think of using Treechat for project managment.
How would you do shared projects? Is that in "private" mode given access to participants or in "public" mode with access to a group of participants?

threads in the home stream are private by default. you can invite others to them by mentioning them... this basically turns that thread to a DM

you can also create private (and public) streams, similar to a slack channel, and invite other users to that stream so that the invited users have access to all threads in the stream

all of the communication to coordinate treechat development happens in treechat