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. Groups are also not fully encrypted, end-to-end. This includes private groups. Private groups cannot be seen by other Telegram users, but Telegram itself can see the groups and all of the communications that you have in them. All of the same risks and warnings about channels can be applied to groups. But Kliuchnikov, the Ukranian now in France, said he will use Signal or WhatsApp for sensitive conversations, but questions around privacy on Telegram do not give him pause when it comes to sharing information about the war. Telegram, which does little policing of its content, has also became a hub for Russian propaganda and misinformation. Many pro-Kremlin channels have become popular, alongside accounts of journalists and other independent observers. But because group chats and the channel features are not end-to-end encrypted, Galperin said user privacy is potentially under threat.
from id