Academia - Did this question have a thank-you note added by somebody other than the person who asked it?

The OP mistakenly posted that additional text as an answer. Moderators can directly convert such non-answers to a comment or an edit to the question. The edit is automatically attributed to the moderator who performed the action (me in this case).

This action can be seen from the question's timeline, accessible by clicking on the clock icon below the question's score:

The action is represented by two rows in the timeline: first the deletion and then the edit (users with less than 10k reputation will only see the edit event).

The edit matches, word for word, what the OP of the question posted as an answer. A moderator (Massimo Ortolano) deleted that "answer" (presumably since it does nothing to answer the question) and incorporated it into the question itself. That seems appropriate, and better than leaving the non-answer as-is or deleting it outright.