Fans of the two were quick to comment on the funny gesture, writing things like, "Friendship goals forever," "Is that a famed frame of you and Matt in the background?" and "I hope this 'feud' never ends."
The famous fake feud has been one of the most long-running gags in late night television, dating back to the early 2000s. It all started with an improvised joke during the third season of Kimmel's show, Jimmy Kimmel Live!, in which he apologized for not having enough time to interview Damon -- calling out the show's lack of A-list guests. Because the joke was so well-received by the audience and one of the producers, Kimmel made a habit of using Damon's name at the end of each episode.
"The legs on this bit are unbelievable to me," Kimmel told NPR in 2013. "I mean, people laugh every time I say it. … Repeating the same joke every single night, you'd think eventually people would get tired of it, but they don't."
While Kimmel has already made it clear he hasn't forgotten his pals birthday, one person we're still waiting to see a celebratory post from is Pink -- her 5-year-old daughter, Willow, has a huge crush on the Massachusetts native!
While chatting with ET in May, the pop star revealed she's actually gotten "in trouble" for telling people about Willow's infatuation with Damon.
"She's already upset with me because there's a new game we play called Ask Siri -- which, she just found out last week there's a Siri -- and I said, 'Siri, Willow-Matt Damon' and all this stuff came up," Pink explained. "[Willow]'s like, 'How do they know?' She got mad at me!"
Hear more on Willow's adorable obsession in the video below.