John Mayer Taylor Swift
Credit: Theo Wargo/WireImage

Dec. 13 is an average day of the year for most people, except for Taylor Swift and her loyal friends, family, and fans, who celebrated the musician's 27th birthday on Tuesday. But one of Swift's famous exes definitely does not celebrate the day in the same way, and John Mayer had some thoughts about her birthdate, which he expressed via Twitter.

"Tuesday, December 13th may be the lamest day of the year, conceptually," Mayer wrote yesterday, before ultimately deleting it because, well, the message was a bit obvious. But, thanks to the wonders of technology and the ability to screenshot, the tweet will live on forever.

Dear John, we see it all now, even though you thought that tweet was gone.

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Swift laid relatively low on her birthday, with no social media posts directly from the songstress, and only a few from some of her famous friends like Gigi Hadid and Karlie Kloss.

Way to throw some serious shade, John, but let's be honest, nothing will be as good as Swift's song "Dear John," which was probably just as obvious as Mayer's tweet, but definitely more elegant, and definitely more hard-hitting.

Happy belated birthday to Swift! Not even a bitter ex can kill her vibe these days.