This policy is deprecated, and slated for removal in Chrome 78, with no replacement.
This policy enables HTTP/0.9 on ports other than 80 for HTTP and 443 for HTTPS.
This policy is disabled by default, and if enabled, leaves users open to the security issue https://crbug.com/600352.
This policy is intended to give enterprises a chance to migrate existing servers off of HTTP/0.9, and will be removed in the future.
If this policy is not set, HTTP/0.9 will be disabled on non-default ports.