headers

Response: Headers.

Provides a typed view of headers associated with this HTTP response, via FetchHeaders, which behaves as a specialized JavaScript-compatible multi-map. Multiple header values can be expressed per header key, if desired, which can be safely combined into a comma-separated header value group upon render.

From MDN: "The headers read-only property of the Response interface contains the Headers object associated with the response."

See also: MDN, Response.headers.