A content author is making changes to a page and would like to create a version with its current state before proceeding with editing
One should go to Sites navigation UI, switch the left toolbar to Timeline, create the version and return to the editor
It is possible to create the version without leaving the editor. I see two ways how it could look: 1) there is a new "Create version" item in the "Page information dropdown"; 2) in "Page information" dropdown, when you select "Start workflow", there is an out-of-the box "Create page" workflow model you can pick. Please see pictures for both options attached.
Environment Details (AEM version/service pack, any other specifics if applicable):