For example, WhatsApp restricted the number of times a user could forward something, and developed automated systems that detect and flag objectionable content. Messages are not fully encrypted by default. That means the company could, in theory, access the content of the messages, or be forced to hand over the data at the request of a government. Individual messages can be fully encrypted. But the user has to turn on that function. It's not automatic, as it is on Signal and WhatsApp. In 2018, Russia banned Telegram although it reversed the prohibition two years later. "Someone posing as a Ukrainian citizen just joins the chat and starts spreading misinformation, or gathers data, like the location of shelters," Tsekhanovska said, noting how false messages have urged Ukrainians to turn off their phones at a specific time of night, citing cybersafety.
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