According with RFC2616 https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2
"Multiple message-header fields with the same field-name MAY be present in a message if and only if the entire field-value for that header field is defined as a comma-separated list [i.e., #(values)]. It MUST be possible to combine the multiple header fields into one "field-name: field-value" pair, without changing the semantics of the message, by appending each subsequent field-value to the first, each separated by a comma. The order in which header fields with the same field-name are received is therefore significant to the interpretation of the combined field value, and thus a proxy MUST NOT change the order of these field values when a message is forwarded. "

If I understand correctly, it should understand a header "h-Bob: v1-Bob, v2-Bob" as two values "v1-Bob" and "v2-Bob". But it actually understands as a single value "v1-Bob, v2-Bob"

I will attach the sample code and corresponding data. This is just a simple request/respone, but needs server to return a multi-value header.