Merge pull request #1950 from return42/about-opensearch

  <h2 id='add to browser'>How to set as the default search engine?</h2>

  <dt>Firefox</dt>

  <p>

    Searx supports <a href="https://github.com/dewitt/opensearch/blob/master/opensearch-1-1-draft-6.md">OpenSearch</a>.

    For more information on changing your default search engine, see your browser's documentation:

  </p>

  <dd>

    <a href="#" onclick="window.external.AddSearchProvider(window.location.protocol + '//' + window.location.host + '{{ url_for('opensearch') }}');">Install</a>

    searx as a search engine on any version of Firefox! (javascript required)

  </dd>

  <ul>

    <li><a href="https://support.mozilla.org/en-US/kb/add-or-remove-search-engine-firefox">Firefox</a></li>

    <li><a href="https://support.microsoft.com/en-us/help/4028574/microsoft-edge-change-the-default-search-engine" >Microsoft Egde</a></li>

    <li>Chrome based browsers <a href="https://www.chromium.org/tab-to-search">only add websites that the user navigates to without a path.</a>

  </ul>

  <h2>Where to find anonymous usage statistics of this instance ?</h2>