Signal tests usernames that keep your phone number private

https://www.bleepingcomputer.com/news/software/signal-tests-usernames-that-keep-your-phone-number-private/

https://twitter.com/home/status/1722504251400741339

https://twitter.com/home/status/1722507132329672951

https://twitter.com/home/status/1722527754053206058

https://twitter.com/home/status/1722544553033449527