Earlier this week, Greta Thunberg was named Time magazine's Person of the Year, after condemning world leaders for not doing enough to combat the climate crisis back in September.
"People are suffering, people are dying, entire ecosystems are collapsing. We are in the beginning of a mass extinction and all you can talk about is money and fairy tales of eternal economic growth," Thunberg said in her now-famous speech.
In an equally memorable moment, the 16-year-old was later caught glaring at President Donald Trump - who reportedly said that climate change was a hoax invented by China.
Check out the moment Greta condemned world leaders for their lack of action before staring down President Trump:Needless to say, Greta and the US president are hardly each other's biggest fans. And so when Trump learned that the teenager had been named Time magazine's Person of the Year, he responded to the decision by branding it "ridiculous" and suggesting that Greta has an anger management problem.
"So ridiculous," Trump tweeted. "Greta must work on her Anger Management problem, then go to a good old fashioned movie with a friend! Chill Greta, Chill!"
In true Greta fashion, she did not take the dig lying down, but also refrained from giving the tweet attention by directly replying to it.
Instead, the Swede changed her Twitter bio to read, "A teenager working on her anger management problem. Currently chilling and watching a good old fashioned movie with a friend."
And this certainly isn't the first time Greta has trolled Trump by quoting him in her Twitter bio.
When her speech at the UN Climate Summit began circulating online, the president sarcastically tweeted: "She seems like a very happy young girl looking forward to a bright and wonderful future. So nice to see!"
So, of course, Greta quoted his tweet in her bio: