domain("foo.ba_r") returns True, and domain("example.co_uk") does too. hostname("foo.ba_r") and email("a@foo.ba_r") return True as well.
An underscore belongs in a service label, and those already require rfc_2782. example_.com is rejected until that flag is set. The last label still allows _ with the flag off.
Reactions are currently unavailable
domain("foo.ba_r") returns True, and domain("example.co_uk") does too. hostname("foo.ba_r") and email("a@foo.ba_r") return True as well.
An underscore belongs in a service label, and those already require rfc_2782. example_.com is rejected until that flag is set. The last label still allows _ with the flag off.