kumomta/docs/reference/addressheader/user.md

user

local user = addressheader.user

If the address header consists of a single simple address, returns the mailbox portion of the address. For example, if the address is "first.last@example.com", addressheader.domain will evaluate as "first.last".

If the address header is not a single simple address, raises an error.

See also addressheader.domain, addressheader.name.

{{since('2026.04.09-ea3b2a9b')}}

The user field now returns the normalized/decoded local part. Previously, quoted local parts such as "quoted"@example.com were returned with the RFC 5322 quoting intact (e.g. "quoted"); they now return the decoded semantic value (e.g. quoted). The same applies to entries in addressheader.list.