Delta Chat on Nostr: are telegrams secret 1:1 chats still leaking to the cleartext network layer? Or did ...

are telegrams secret 1:1 chats still leaking to the cleartext network layer? Or did they finally use it on top of their custom transport encryption which is also known to have flaws? Even if they fixed it by now there are no e2ee group chats so there simply is no reasonable comparison to Signal and other messengers who offer pervasive e2ee automatically.