Server Permissions

By disabling "Read message history" the current users who were already sent messages in the past they won't be able to see it again.

So i suggest to make a start point of the history of messages,Example: user#7875 joined a channel "make the start/return point from the first message he sent where he can see history of messages which previously viewed when he was in,but he can't see what was before he joins,only he can see after his first message in that channel.