> Telegram provides a feature called "Links previews" that's available and on by default in not encrypted chats, anyways if you use a "Secret chat", Telegram ap

> Telegram provides a feature called "Links previews" that's available and on by default in not encrypted chats, anyways if you use a "Secret chat", Telegram app ask to you if you want to use "links previews" adversiting that it previews are done in the server side. How can they know what links are you writing? Can they read your messages still if you are using "Secret chats"? (Not sure but is a edge case). It feels reasonable to assume the Telegram client detects the links (using a regexp or something) and sends them to the server side. Of course they see the links if you ask them to but this doesn't mean they also see all the text.