Say there are two revisions:
#2 mine
#1 OP [edit]
What used to happen, if I pressed edit next to the first revision, added stuff to #1 (not #2), they would be like this:
#3 rollback -- [manual comment if any]
#2 mine
#1 OP
That did not happen here (#3) as it used to; moreover, the OP title and OP tags were not reverted, even though the editing page included them: