See updates and previous versions on a shared page
WebNew
When you return to a file while signed in, its shared page now shows version updates and new comments since your previous visit. Select the version update to open version history, or select the new comment count to open the comments panel.
From version history, you can open any published previous version of an HTML page, Markdown document, or static site and see its contents at that point in time. A notice remains visible while you are viewing a previous version, so you can return to the current version at any time. The selected version is preserved when you reload the page or use your browser's back and forward buttons.
To compare it with the current version, open the previous version link in another browser tab or window.