Feature Request: Stash the previous post type

[JJJ]

See: https://wordpress.org/support/topic/featured-request-keep-a-copy-of-the-original-post-type/

This poses a number of engineering challenges due to how the Revisions API works, and the facts that not-all-post-types support them and they can be totally disabled & filtered to do weird stuff.

I think it'll just be easiest to keep it very simple instead; stash the last post_type value in wp_postmeta, and only use that value to add some emphasis on the GUI elements, to introduce a very-very-very simple "revert" or "undo" or "this used to be" kind of hint.

I'm not certain that going back & forth multiple times is the most common path, but I am aware that users do like to test the limits of this plugin and the best way to do that is to change something and then change it back, so I can imagine how some awareness of that would be helpful!