Restore from autosave does not revert changes in pages (but story data is restored)

Bug Description

Restoring an autosaved webstory that is different from the local version does not work in reverting changes to pages. However, a change in the story data (like title) is reverted !

Expected Behaviour

Steps to Reproduce

The following steps consistently reproduce the problem:

1. Create a new story with 1 page
2. Publish it with poster and description etc
3. Add another page and move it to first position
4. Update this story
5. Now add a third page, change the title & wait for a min to create the autosave session key
6. exit to dashboard without saving to DB
7. reopen the now published & updated story
8. you will get two overlays - one for restoring from local backup (dismiss this) and another for restoring from saved version …
9. Here, view the different versions and restore the latest (3 slides)

ISSUE: the version with 2 slides is restored instead of the last saved version

Screenshots

Additional Context

This issue was observed in #12521 as well.

• Plugin Version: main branch as of 10/25/2022
• WordPress Version: 6.0.3
• Operating System: Win10
• Browser: Chrome

[swissspidy]

cc @miina who worked on this

[kkalarickal]

@swissspidy - regarding the two dialogs … Comparing the way autosave/local-backup behaves for WP Post with how its implemented in web stories, it appears that after local changes are made to a draft, if the user exits the editor:

• in the WP post case, the changes are saved to disk and the local-session backup is deleted
• in the WebStories case, the changes are saved to disk but the local-session backup is retained

This is ok so long as the story is not published. Because after published status, the changes made after autosave are not written to db when exiting the editor. So now there is a legitimate difference between the local-session backup and the story in db which is why we have two dialogs (correctly).