I have a similar issue on Github and Gitlab.com - my handle there (same as here) overlaps with a certain annotation from Java's Hibernate, so I get a lot of @mentions from random repos.
(And all that because Github and Gitlab are both case-insensitive when matching @mentions.)
A lot of this is automatic - someone uses the proper @Annotation in a commit messages or pull request name, and I get an e-mail that I was just mentioned in some random repo.
(And all that because Github and Gitlab are both case-insensitive when matching @mentions.)