Allow users to discard their own changes with Collaborative Editing

Problem statement

With Collaborative Editing enabled, all users are sharing the same draft. However, if a single user wants to leave the editor and discard his own changes, he doesn't have the option to do so unless:

1. He manually removes his changes.
2. He clicks on the 'Undo' button in the page until his changes are gone.

At present, he can only either remove everyone's changes or keep everyone's changes along with his own.

Suggestion

1. Provide an extra button or option ("Discard my changes") whereby the user can discard his own changes.
2. Include the user's names and their changes when reverting option is clicked so that the person who wants to revert the changes, is aware of the removal of the other users' changes as well.