RFC 7239, "Forwarded HTTP Extension", June 2014

Errata ID: 5275
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: W. Trevor King
Date Reported: 2018-03-06

Section 4 says:

Forwarded   = 1#forwarded-element

It should say:

Forwarded   = forwarded-element *(OWS "," OWS forwarded-element)
OWS = <Defined in [RFC7230], Section 3.2.3>

Notes:

Currently the only mention of commas in the RFC is in the text:

> A proxy server that wants to add a new "Forwarded" header field value can either append it to the last existing "Forwarded" header field after a comma separator or add a new field at the end of the header block.

This should be reflected in the ABNF. The original ABNF suggests you just smash the forwarded-elements together with no delimiters.

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