CNN — The unprecedented protests that swept China late last month, posing the biggest challenge to leader Xi Jinping’s authority since he came to power, had a peculiar focal point: a Chinese Twitter account with a cat avatar. As people took to the streets to call for greater freedoms and an end to zero-Covid restrictions, the account “Teacher Li is Not Your Teacher” live-tweeted the demonstrations in real-time, offering a rare window into just how quickly and widely the eruption of dissent reverberated across the country. Inside China, videos, photos and accounts of the protests were swiftly censored online. But…