Relates to Side-by-side view
The ability to view different versions of a note side by side would make it much easier to see what has changed. I could have done with this a few months back when I was reorganising and found I'd lost some information that was only in an old version of a note.
Or at least let users set up a Diff program that's called so Joplin developers won't have to worry about writing a Joplin version of Diff. I use Beyond Compare and it would be great if I could call out to that to compare two versions of a note.
I think I mentioned at one point that the conflict resolution plugin could be adapted to allow that. But I am not sure if the dev ever implemented anything in that regard.