Jeff Waugh

Add OpenSearch discovery and querying to your WordPress site, based on the 
<a href="http://www.opensearch.org/Home" rel="nofollow ugc">OpenSearch</a> specification, version 1.1.
After activating the plugin, your WordPress site will expose a standardised 
search interface, accessible to OpenSearch clients such as the <a href="http://www.mozilla.com/firefox/search.html" rel="nofollow ugc">Firefox 
search bar</a>.

OpenSearch

Add OpenSearch discovery and querying to your WordPress site.

Matthias Pfefferle

The plugin creates an OpenSearch Document for your blog.
It supports Google Chromes <a href="https://www.chromium.org/tab-to-search" rel="nofollow ugc">“Tab to Search”</a> and <a href="https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/chrome_settings_overrides" rel="nofollow ugc">“search_provider” WebExtension</a>, Firefox’ <a href="https://developer.mozilla.org/en-US/docs/Web/OpenSearch" rel="nofollow ugc">“OpenSearch plugins”</a>, Safaris <a href="https://developer.apple.com/library/content/releasenotes/General/WhatsNewInSafari/Articles/Safari_8_0.html" rel="nofollow ugc">“Quick Website Search”</a>, and <a href="https://support.microsoft.com/en-us/microsoft-edge/change-your-default-search-engine-in-microsoft-edge-cccaf51c-a4df-a43e-8036-d4d2c527a791" rel="nofollow ugc">“custom searches”</a> for Microsofts Edge browser.
From the <a href="http://www.opensearch.org/Specifications/OpenSearch/1.1" rel="nofollow ugc">spec</a>:
<blockquote>
Search clients can use OpenSearch description documents to learn about the public interface of a search engine. These description documents contain parameterized URL templates that indicate how the search client should make search requests. Search engines can use the OpenSearch response elements to add search metadata to results in a variety of content formats.
</blockquote>
Other integrations and extensions:
<ul>
<li>Extension links for <a href="http://www.opensearch.org/Specifications/OpenSearch/1.1#Autodiscovery_in_HTML.2FXHTML" rel="nofollow ugc">HTML</a>, <a href="http://www.opensearch.org/Specifications/OpenSearch/1.1#Autodiscovery_in_RSS.2FAtom" rel="nofollow ugc">Atom and RSS</a></li>
<li>Autodiscovery via <a href="https://wordpress.org/plugins/xrds-simple/" rel="ugc">XRDS-Simple</a>, <a href="https://wordpress.org/plugins/host-meta/" rel="ugc">host-meta</a> and <a href="https://wordpress.org/plugins/webfinger/" rel="ugc">WebFinger</a></li>
<li><a href="http://www.opensearch.org/Specifications/OpenSearch/1.1#Examples_of_OpenSearch_responses" rel="nofollow ugc">RSS and Atom search responses</a></li>
<li><a href="http://www.opensearch.org/Specifications/OpenSearch/Extensions/Suggestions/1.0" rel="nofollow ugc">OpenSearch Suggestions extension</a></li>
</ul>

Open Search

This plugin is easy to use. Install it and it works :)

Do what it should

Maybe an gif animation for the visitors which is linked to a desccription howto use would be nice.
i would like to translate to german.

thanks for the update, why not used on more webpages?

Create an OpenSearch Document for your blog.

OpenSearch vs Open Search