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. Channels are not fully encrypted, end-to-end. All communications on a Telegram channel can be seen by anyone on the channel and are also visible to Telegram. Telegram may be asked by a government to hand over the communications from a channel. Telegram has a history of standing up to Russian government requests for data, but how comfortable you are relying on that history to predict future behavior is up to you. Because Telegram has this data, it may also be stolen by hackers or leaked by an internal employee. Perpetrators of such fraud use various marketing techniques to attract subscribers on their social media channels. 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. Now safely in France with his spouse and three of his children, Kliuchnikov scrolls through Telegram to learn about the devastation happening in his home country.
from fr