

Not necessarily. I’m not some sort of tech genius but she’s using some choice language here:
push notifications for Signal NEVER contain sensitive unencrypted data & do not reveal the contents of any Signal messages
metadata is not “contained” in the notification.
When pushed on this she basically changed the subject to “there’s no alternative”:
Another Twitter user pointed out that rather than the exposure of the text, the bigger issue is that “the push gets sent at all, not what’s in it. It lets an attacker identify somebody by when they get messages, messages the attacker may even have sent.”
To this, Whittaker replied, “So this is an issue worth clarifying. It’s not possible [right now] to build a mass [communications] app [without] push notifications, [especially with] calling. This is a problem, we agree.”
https://www.medianama.com/2023/12/223-signal-push-notifications-content-meredith-whittaker/
I could be misinterpreting these statements but that’s how it reads to me. Seems like encrypting metadata would require Google’s involvement and I’m sure that’s the opposite of what they want.
I actually like Mattermost as a free slack alternative. Matrix is too complicated for normies and the encryption seems unnecessary on a local server.