[FabHK]

To be fair, what other simple way is there to send a document to a contact through an e2ee channel? Mail + PGP/GPG? Wormhole?? openssl???

Sending it via WhatsApp (which also has desktop clients, btw) strikes me as a perfectly reasonable solution. (Which is somewhat of an indictment of the current state of cryptographic software, but that's a different topic.)

[LtWorf]

Whatsapp "claims" to be e2e, but nobody knows for sure since its sources are closed.

[prmoustache]

Still more secure than non encrypted email yet a lot of people still use email to send fairly sensitive data.

[account42]

Email doesn't go through an app controlled by Facebook so I don't agree about your security assessment.

[FabHK]

You don't know where your email goes through, and email for sure is not end to end encrypted.

WhatsApp uses the Signal protocol. Closed source code can be decompiled, open source does not magically give you better security properties.

[LtWorf]

> WhatsApp uses the Signal protocol

claims to do so.

> open source does not magically give you better security properties.

Reproducible builds do, in fact I have no idea if you and I are running the same whatsapp at all.