Don't advertise pingback URL on resources that don't support pingbacks
|Reported by:||solarissmoke||Owned by:|
Currently, WordPress indiscriminately adds an X-Pingback header to all responses. Similarly all the bundled themes add link rel="pingback" to all pages.
The purpose of X-Pingback and link rel="pingback" is to advertise that the current resource supports pingbacks and provide a pingback URL. They should only be inserted when the resource actually accepts pingbacks - i.e., only when is_single() is true, and maybe even only when pings are open on that post.