@Tutanota This is kind of clickbait. A less manipulative headline would qualify that it leaks the IP to _the recipient_ of the call and that this is due to the VoIP protocol being _peer to peer_.
I won't argue that Signal is a more secure app, but Peer to Peer calling is not a security vulnerability. Many security focused people would consider peer to peer VoIP desirable. Especially since the alternative is the calls going through Telegram's servers
@Tutanota TBH when looking into this I was both surprised and disappointed to discover that Signal calling wasn't peer to peer.