New direct chats should be visible to the invited participant
If I create a new direct chat with someone, and start typing before that person joins the room, my messages will not be visible to the recipient. I have to log in to Riot and change the message visibility status for the room before the recipient will be able to see the messages.
Worse, there is no indication that the recipient is not actually receiving the messages.
The default visibility for direct chats created by Fractal should probably be: members only (since the time they were invited).