Should I Confront My Partner's Friend?

My (29F) partner's friend (33M) has been overly flirtatious with me whenever we hang out together. At first, I thought I was just imagining things, but it's becoming more noticeable. I feel uncomfortable but also awkward bringing this up to my partner. Should I talk to my partner about this? Or am I overreacting? How do you handle situations involving friends of your significant other? #WhatWouldYouDo #RelationshipAdvice #Boundaries