I'm pretty sure the owner of the “Mozilla Team” team PPA [1] has been dead since 2013 [2]. He is also listed as an Administrator. If someone were to comprise his account via his old email, e.g. if he used a now expired domain that could be registered, they could use this PPA to deliver a backdoored Firefox build to thousands of users and steal their passwords, tokens and SSH keys.

Community support is great but without a proper security team and enforced secutiry processes the PPAs are very dangerous.

[1] https://wiki.ubuntu.com/JohnVivirito

[2] https://www.dignitymemorial.com/obituaries/apex-nc/john-vivi...