sol2/sphinx_rtd_theme/breadcrumbs.html

<ul class="wy-breadcrumbs">
  <li><a href="{{ pathto(master_doc) }}">Docs</a> &raquo;</li>
  <li><a href="">{{ title }}</a></li>
    <li class="wy-breadcrumbs-aside">
      {% if display_github %}
        <a href="https://github.com/{{ github_user }}/{{ github_repo }}/blob/{{ github_version }}{{ conf_py_path }}{{ pagename }}.rst" class="icon icon-github"> Edit on GitHub</a>
      {% endif %}
      {% if show_source and has_source and sourcename and display_github %}
        &nbsp;&laquo;&nbsp;
      {% endif %}
      {% if show_source and has_source and sourcename %}
        <a href="{{ pathto('_sources/' + sourcename, true)|e }}" rel="nofollow">[source]</a>
      {% endif %}
    </li>
</ul>
<hr/>