When prompting for restoring the backup, a diff should be shown

[koppor]

As user, one is not sure, what is the "backup" version of the ".bib" file. It could even be possible that the backup failed and JabRef destroys data when restoring from the backup (see #9063).

Example popup:

Thus, it would be nice if the dialog offered a button to show the diff. We should have that functionality at the "file changed on disk" notification.

Refs #6190

@HoussemNasri Could you have a look?

[Siedlerchr]

There needs to be warning as well:

WARNING: Restore from backup will overwrite your current library

[koppor]

The diff should also be shown at "Save before closing":

I just opened JabRef, changed a preference - and JabRef told me that there is a diff 🙈

[HoussemNasri]

I'm curious what preferences change the bib file? I see, the citation key patterns are encoded as metadata in the library file.

[koppor]

I'm curious what preferences change the bib file? I see, the citation key patterns are encoded as metadata in the library file.

However, they are "only" stored there if they are changed locally for the bib file. These local ones override the global ones (refs #8701). Thus, I assume nothing should be changed in the bib file if one changes the global preferences.