Today, a user edited an old answer of mine to add a completely different construction to the one I used. There was no indication made into the addition that this was not me writing it (a user would have had to go into the edit history to note this). Here is the edit history
I rolled back. I hope I’m not overreacting; it seems to me that this is the sort of thing that should have been added as a new answer by the editor, not dropped into my answer with no attribution at all (as I indicate in an added comment, it literally puts words in my mouth). Any comments on whether the edit was proper, or my rollback was improper?