

Tbf, Signal, and most modern chat clients with multi-device syncing are not great for opsec.
When it comes to privacy from mass surveillance or using your metadata to mine demographic preferences who you are talking to etc Signal sits at the top of generally available chat clients.
But it’s geared for the convenience and privacy of the average user not military security.
Eg: when it comes to group chats you just have to get one of the members of the chat to fall for a device syncing link, for then the whole group chat future messages to become available to the attacker. What’s more, no admin or other user of the chat gets to have approval or visibility privileges or notification of a new synced device for that chat or any info about the status of each of the devices on that chat.
They have commercial tvs for kiosks, hotels, etc though a bit more expensive don’t have any of that junk.