History puts the site back to an earlier save and publishes that version.
On the website canvas, the history icon opens History. The note under the title says Restore puts the whole site back, including the theme.
In the page editor, open the menu next to Save. Live marks the version on the site. Older rows have Restore.
What Restore does
Restore puts each page back to how it looked at that time and publishes it. It also puts back:
The theme, including colors, type, and site-wide SEO
The header and footer
Navigation
Custom section code
A page that was created after that point stays as it is. A custom section that is already archived is left archived.
The toast is Restored the site to this point.
If the rest of the site cannot be restored, the page editor shows Restored this page. The rest of the site could not be restored. If nothing can be restored, the toast is Could not restore that version.
The restore is saved in History, so you can Restore a later point to undo it.
When the list is empty
History on the canvas says Edits show up here after you change a page.
The menu next to Save says Save this page to start a history.