I googled about the gif. I didn't think I'd find anything funny but I quickly did. Emphasis mine.

For the Love of God, Not Everything Is a Deepfake

Donald Trump retweeted a gif of Joe Biden with his tongue out. No, it's not a deepfake—or the end of democracy.

[...]

This isn't a deepfake. Deepfakes don't stretch and drag facial features like that. As the watermark shows, this video was made using Muglife, which animates images according to how you distort them with a finger—kind of like stretching and pulling an image in Photoshop, but rendered in gif form.

Frum didn’t just tweet about the video, he went and turned it into a blog post for the Atlantic, warning about the dangerous precedent set by Trump sharing a video that has been altered to show his competitor… with a cartoonish tongue.