Comment 6 for bug 28459

I've been hitting this a bit recently, twice in two days, for example in <https://bugs.edge.launchpad.net/bzr/+bug/388675>. It's true that it's not unrecoverable but it does sometimes cause confusion along the lines of "hey, why did you reopen my bug?!?"

I don't think this needs to be very hard to solve, either. Store in hidden fields the original values of the assignee, status, importance, milestone, etc. Then when the form is submitted, only set the fields that were changed relative to the origin.