A version history of Emails in which I can see the date and time of the last “save points”. If I make adjustments in the email or “play around” with various functions, I can jump directly back to a previous version (save point) of the newsletter if I don't like the adjustments after all or if I have done something wrong → Note: Already exists for Journeys.

You may also have a look at confluence. There you can see who made which changes within a document and it's possible to go back to an earlier version.