Mentioned patch

Quite simply, both prop=pageprops and prop=info&inprop=displaytitle try to set "displaytitle" on the returned node: internal_api_error_MWException" info="Exception Caught: Internal error in ApiResult::setElement: Attempting to merge element 25970423

Pageprops should probably have been made to store its values in a subnode, like prop=categoryinfo and basically everything else does to prevent this sort of naming conflict. For example,

<page pageid="25970423" ns="0" title="IPad">
  <pageprops defaultsort="Ipad" displaytitle="iPad" />
</page>

It's a really easy (but breaking) change to do that. I don't know what a good solution would be without introducing a breaking change, especially since it's possible similar conflicts could arise with other page props.

Version: 1.18.x
Severity: normal
URL: http://en.wikipedia.org/w/api.php?format=jsonfm&action=query&prop=info|pageprops&titles=IPad&inprop=displaytitle

Attached: