OpenSearch not working in Firefox: "Firefox could not download the search plugin from"

Question

While testing to ensure OpenSearch works for my site I receive the error, "Firefox could not download the search plugin from:" after clicking the search provider to add it to Firefox.

Here is the source for my OpenSearch looks like...

<?xml version="1.0" encoding="UTF-8"?>
<OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/" xmlns:moz="http://www.mozilla.org/2006/browser/search/">
<ShortName>Example</ShortName>
<Description>Search www.example.com</Description>
<Image height="16" width="16" type="image/vnd.microsoft.icon">http://www.example.com/favicon.ico</Image>
<InputEncoding>UTF-8</InputEncoding>
<Url method="get" template="http://www.example.com/search/?q={searchTerms}&#38;source=opensearch" type="application/xhtml+xml" />
</OpenSearchDescription>

What am I doing wrong that is generating this error?

Answer 1

No text/html Url element:

https://developer.mozilla.org/en/docs/Creating_OpenSearch_plugins_for_Firefox

Note that you must include a text/html URL — search plugins including only Atom or RSS URL types (which is valid, but Firefox doesn't support) will also generate the "could not download the search plugin" error.

I've just had the same problem myself!