Autosaving somehow triggers a full save when metaboxes exist, causing too many revisions

[danielbachhuber]

When there are one or more metaboxes on the page, the autosave process somehow triggers a full save, which then causes the creation of a ton of revisions.

See this GIF:

Notably, see the "Autosaving..." animation, quickly followed by "Saving...". At the end of the experience, 4 revisions have been created (the UI for which is only present after you refresh the page):

Previously #3656 (comment)

cc @adamsilverstein @aduth

[adamsilverstein]

Thanks for opening this issue, I’m out this week. I’ll take a look soon if nobody beats me to it.