The pkgdb webapp used to provide browser search boxes. It's quite useful when I'm looking for a package, I don't need to open pkgdb to fill the search form and I already miss it :-)
You'd need to add a "search" relation  in the HTML head and expose an OpenSearchDescription xml file with the search details.
 <link rel="search" type="application/opensearchdescription+xml" href="..." title="..." />
Fixed in https://git.fedorahosted.org/cgit/pkgdb2.git/commit/?id=53ee47be7b335eaae409a96a2003c462a78662e5 which adds support for searching packagers.
I updated the dev instance if you want to check it: http://126.96.36.199/
Thanks for the enhancement! :)
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