I think everyone would like this. It would be nice if we could go back to the last working configuration of an add-on. Or even XenForo (But that's probably more complicated) I recently had a few problems with add-on's and was unable to go back to the old add-on because the new add-on changed so many things. If XF could register what it changed or backup the changes it could undo them. I think it's perfectly possible, the only thing might be the impact on the DB/Filesystem size. But who cares about a few GB's these days. Of course with a big board it might be tricky if the tables of that add-on are huge. Please like if you agree b.t.w. I always make backups before I update something, and test on my dev forum. Just want to say that before you guys start about it.