If you know the saying "you're only as strong as your weakest link", it may be a good time to reflect on what that means when it comes to online privacy.
To crack the signal cryptography, revealing a key that can decrypt a database where media and messages are stored.
Unlocked android devices, meaning you have not encrypted the devices with any sort of custom hardware level encryption provided by Google or your Chinese Spyware provider Huawei if you are mentally challenged enough to buy a Huawei.
https://www.techradar.com/news/signals-famous-encryption-may-have-been-cracked
If you're using signal, all it takes is 1 person on your contacts list not encrypting their android device to complete compromise both users privacy.