"I had so much love and respect for you until you liked this s---," one critic hurled at the "Chicago Fire" actor.
On Sunday -- the same day Gaga's "Shallow" from "A Star Is Born" won the Oscar for Best Original Song -- Kinney shared a photo of himself and former hockey player Bryan Bickell. He captioned the shot, "Stoked to be out with my guy and his wife for the weekend. 29. Good times in Chicago."
A troll in the comments section replied, "Stoked you got away from Gaga. #Hollyweird" -- and Kinney actually "liked" the comment! After instant backlash from Gaga stans and fans alike, the actor left a new comment, apologizing.
"Imagine being bitter and liking shady comments after someone's success," one person jabbed. "I had so much love and respect for you until you liked this shit. Way to trash someone you were once going to marry."
"Sorry for the 'like.' It was an accident," Kinney explained. "I'm only proud and happy for Stef."
Gaga, whose real name is Stefani Germanotta, was engaged to Kinney from Valentine's Day 2015 to shortly after she landed her role in "A Star Is Born" in 2016. They were together for five years before the actor popped the question.
But it never seemed like there was any bad blood between the two. In fact, shortly after the split, the pop star released a statement that said, "Taylor and I have always believed we are soulmates. Just like all couples, we have ups and downs, and we have been taking a break."
In her 2017 documentary, "Gaga: Five Foot Two," the singer broke down in tears while discussing the breakup, alluding to the fact that her thriving career may have been a contributing factor.
"I did a movie and lost Taylor," she said. "This is the third time I've had my heart broken like this."
Gaga was most recently engaged to talent agent Christian Carino, but the couple announced their split earlier this month. Many people thought Gaga's on-screen love interest Bradley Cooper had something to do with it, but she dispelled those rumors during her Wednesday night appearance on "Jimmy Kimmel Live."
When the late-night host brought up the touchy subject, the singer rolled her eyes and said, "First of all, social media, quite frankly, is the toilet of the internet. And what it has done to pop culture is just abysmal."
With that as her starting point, Gaga went on to explain that people saw exactly what she and Cooper wanted them to see. "People saw love, and guess what? That's what we wanted you to see," she said. "This is a love song, 'Shallow.' The movie, 'A Star is Born' -- it's a love story. From a performance perspective, it was so important to both of us that we were connected the whole time. When you're singing love songs, that's what you want people to feel."
Cooper's ex-wife, former "NCIS" star Jennifer Esposito, also came under fire for replying to a comment comedian David Spade's left on an Instagram photo of the co-stars' Oscars performance. "Is there any chance these two aren't f--king?" he wrote, to which Esposito replied, "Ha!"
One person who surely wasn't laughing was Cooper's longtime girlfriend and baby mama Irina Shayk, but she's remained mum on the whole thing.
After being slammed, dragged and insulted by hundreds of people for her two-letter comment, Esposito addressed the issue in an Instagram video she shared Tuesday.
"So many people have been commenting about something that I said, was which was like this, ready? 'Ha!' That was it," she said, emphasizing how ridiculous she believes the response has been. "I'm allowed to think something is funny."
"We have so many things going on in our country and our world that need attention, and I wish that you'd spend even a minute of this insanity of nonsense on things that are really important," she added before turning her attention to the women she's encountered who've made their attacks personal.
"For other females to come after another female for saying 'ha' and how I'm an old lady and I need to feel relevant: I didn't watch the Oscars, I don't know what went on, I don't care what went on," she concluded.
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