Editor: Post contains local changes even when the user doesn't modify the post

[malinajirka]

Expected behavior

When I open a post in the gutenberg editor and I close it I expect the post won't contain any local changes.

Actual behavior

When I open a post in the gutenebrg editor and I close it the post contains local changes.

Steps to reproduce the behavior

1. My Site
2. Blog Posts
3. Open a published post (eg. this long post) - it happens on some posts only after you click into the content. However, it happens on this post even when I just open it and close it)
4. Press back
5. Notice the post contains "Local changes" label

Tested on [device], Android [version], WPAndroid [version]

Emulator API 29

cc @mchowning you recently played with saving/exiting editor
cc @planarvoid you also have context. Would you have time to look into it during groundskeeping?

[hypest]

Looks related to the ticket opened a few days ago in the gb-mobile repo: wordpress-mobile/gutenberg-mobile#2714

[malinajirka]

Thanks for the info, I've missed that. They look similar, however, I haven't even need to scroll + this issue isn't about autosave but about save on exit. Having said all that there is a pretty high chance these two tickets are related.

[planarvoid]

Since you're also @mchowning doing groundskeeping this week, is it ok if I'll leave this to you?

[mchowning]

@mkevins has noted a similar-sounding issue here:

Another observation [...] is that simply opening and existing the post (without making any changes) and then closing it results in the autosave mechanism kicking in.

[mchowning]

I have spent some time investigating this, and it appears to be due to certain blocks having outdated or otherwise unexpected (but valid) formatting in the post content. I (obviously) still need to do some more investigation into this, and I do plan to follow-up on this.

[mchowning]

I suspect this may be related to wordpress-mobile/gutenberg-mobile#894.

[malinajirka]

A note which might be useful - I noticed the EditorFragment.getTitleOrContentChanged() is invoked when you open a post. It's also interesting that it is invoked on the same post every time you open it (even if you open it after it already has the "local changes" label).

[mchowning]

Removed my assignment because I'm not going to have time to get back to this in the near future.