Well, I knew my brother was getting a new phone soon anyways so getting notified his device changed wasn’t a surprise. Otherwise, getting notified hia device changed without that knowledge may have triggered me to contact him elsewhere to ask if he did. Signal is mostly going to be conversations between close/trusted individuals. It doesn’t tell you what they changed to, the message basically tells you that if this person didn’t legitimately change devices then it might be a bad actor.

I knew my brother got a new phone because signal told me their usual device had changed.

I was using Firefox then swapped to mull. Both are good, i just figured I’d try something different and saw mull on fdroid.