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# HTTP/2 and Header Casing

We have started deploying new infrastructure that supports HTTP/2 connections.
The [HTTP/2 specification](https://tools.ietf.org/html/rfc7540#section-8.1.2)
requires lowercase headers and
[HTTP/1.1](https://tools.ietf.org/html/rfc2616#section-4.2) states header names
are case insensitive. Therefore, we have updated our documentation to specify
lowercase header names but will continue to support case insensitive headers in
requests for HTTP/1.1 connections. Responses will have header names normalized
to lowercase.