Further following the great move of the new contributor indicator, maybe the "possible duplicate" automatic message should be nicer. Personally, I edit this comment into something like:
Hi and welcome to Stack Overflow :) This question is a possible duplicate of yada yada. WDYT?
This improved version of the comment will appear only to new contributors. For "old" users it will remain the same.
Here's a similar but not identical or duplicate question: Friendlier wording for automatic "possible duplicate" comment?