TE
The transfer codings the user agent is willing to accept.
Fastly reads this header from requests and writes it into requests. It is defined by an external standard.
PROTECTED: This header cannot be modified in VCL.
The TE header field in a request indicates what transfer codings, besides chunked, the client is willing to accept in response, and whether or not the client is willing to accept trailer fields in a chunked transfer coding.
The TE field-value consists of a comma-separated list of transfer coding names, each allowing for optional parameters (as described in Section 4 of RFC 7230), and/or the keyword trailers. A client MUST NOT send the chunked transfer coding name in TE; chunked is always acceptable for HTTP/1.1 recipients.