I haven't read the original article... paywall... but I have read other versions of the story, such as: https://www.theverge.com/2020/3/8/21170714/twitter-manipulated-media-biden-video-retweeted-trump
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More recently:
https://www.nytimes.com/2020/03/09/technology/manipulated-biden-video-trump.htmlWASHINGTON — A manipulated video featuring Joseph R. Biden Jr. and spread by President Trump over the weekend has ratcheted up an online war that has put Twitter and Facebook in the middle of a debate over political speech.
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The video came from a stump speech by Mr. Biden on Saturday in Kansas City, Mo., where he appeared to struggle through a sentence and with halting words said, “We can only re-elect Donald Trump.”
But the rest of Mr. Biden’s sentence was selectively edited out. In full, Mr. Biden was stressing the need for Democrats to unite against Mr. Trump.
“We can only re-elect Donald Trump if in fact we get engaged in this circular firing squad here. It’s got to be a positive campaign,” he said.