For what it's worth, the late Dmitry Zapolsky hinted in his book Putinburg that Pavel Durov worked with the FSB from the beginning of his entrepreneurial career in Russia.
Cmon telegram is NOT an fsb operation
If you trust the encryption of it though, you are an idiot
I don’t think the author ever defines what FSB means.
At least he’s honest this is just his gut hunch, and not backed by any public or unreleased information
The Russian federal security service, essentially what the KGB turned into.