eg. https://musicbrainz.org/edit/59656275

This shows the current information but not the information as it was at the time. Whatever information that is displayed for editing history purposes (in this case I think title artists disambiguation & group title artists disambiguation) should be stored in the edit record.

https://musicbrainz.org/edit/6892911

This artist later had a disambiguation added. Any such disambiguation should be added to the edit record at the time and only displayed if it is there.

Similarly, each type of edit needs correcting in the same way. I suggest the data is stored in a single field which could even include line breaks and links (the edit history enquiry would need to be able to handle clicked dead links).