"German court documents yesterday revealed that French intelligence has access to all of Telegram's internal data now, thanks to Durov. They are freely sharing it with other intelligence & police agencies, so warrants aren't even needed."
Telegram is fully compromised.
There is no source given for this one on the original tweet.
But it’s not surprising. It was suspected that Durov complies after his arrest in France a while back. It’s more of a reminder that his happened.