RFC2616 section 4.2:
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.
Nothing is wrong this is correct.
2
HTTP 1.1 allows multiple Connection headers. The semantics of multiple such headers are defined to be the same as a single header with all values joined together with commas, e.g.
Connection: close Connection: keep-aliveis the same as:
Connection: close,keep-alive
Also permitted
According with paragraph 4.2 of RFC2616 (HTTP/1.1), field values might be preceded by whitespace, but not the field name:
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