lib/source/layouts/core.erb

<!doctype html>
<html lang="en" class="govuk-template no-js">
  <head>
    <meta content="IE=edge" http-equiv="X-UA-Compatible">
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, viewport-fit=cover">

    <title><%= meta_tags.browser_title %></title>

    <%= stylesheet_link_tag :manifest %>

    <link rel="canonical" href="<%= meta_tags.canonical_url %>">
    <link rel="icon" sizes="48x48" href="/assets/govuk/assets/images/favicon.ico">
    <link rel="icon" sizes="any" href="/assets/govuk/assets/images/favicon.svg" type="image/svg+xml">
    <link rel="mask-icon" href="/assets/govuk/assets/images/govuk-icon-mask.svg" color="#0b0c0c">
    <link rel="apple-touch-icon" href="/assets/govuk/assets/images/govuk-icon-180.png">
    <link rel="manifest" href="/assets/govuk/assets/manifest.json">

    <% meta_tags.tags.each do |name, content| %>
      <%= tag :meta, name: name, content: content %>
    <% end %>

    <% meta_tags.opengraph_tags.each do |property, content| %>
      <%= tag :meta, property: property, content: content %>
    <% end %>

    <%= yield_content :head %>
  </head>

  <body class="govuk-template__body">
    <script>document.body.className += ' js-enabled' + ('noModule' in HTMLScriptElement.prototype ? ' govuk-frontend-supported' : '');</script>

    <div class="app-pane">
      <div class="app-pane__header toc-open-disabled">
        <a href="#content" class="govuk-skip-link" data-module="govuk-skip-link">Skip to main content</a>

        <%= partial 'layouts/header' %>
      </div>

      <% if content_for? :sidebar %>
        <div id="toc-heading" class="toc-show fixedsticky">
          <button type="button" class="toc-show__label js-toc-show" aria-controls="toc">
            Table of contents <span class="toc-show__icon"></span>
          </button>
        </div>
      <% end %>

      <div class="app-pane__body"<%= " data-module=\"#{yield_content(:toc_module)}\"" if content_for? :toc_module %>>
        <% if content_for? :sidebar %>
          <div class="app-pane__toc">
            <div class="toc" data-module="table-of-contents" tabindex="-1" aria-label="Table of contents">
              <%= partial "layouts/search" %>
              <button type="button" class="toc__close js-toc-close" aria-controls="toc" aria-label="Hide table of contents"></button>
              <nav id="toc" class="js-toc-list toc__list" aria-labelledby="toc-heading"<%= " data-module=\"collapsible-navigation\"" if config[:tech_docs][:collapsible_nav] %>>
                <%= yield_content :sidebar %>
              </nav>
            </div>
          </div>
        <% end %>

        <div class="app-pane__content toc-open-disabled" aria-label="Content">
          <main id="content" class="technical-documentation" data-module="anchored-headings">
            <%= yield %>
            <%= partial "layouts/page_review" %>
          </main>

          <aside>
            <% if config[:tech_docs][:show_contribution_banner] %>
              <ul class="contribution-banner">
                <li><%= link_to "View source", source_urls.view_source_url %></li>
                <li><%= link_to "Report problem", source_urls.report_issue_url %></li>
                <li><%= link_to "GitHub Repo", source_urls.repo_url %></li>
              </ul>
            <% end %>
          </aside>

          <%= partial "layouts/footer" %>
        </div>
      </div>
    </div>

    <%= partial 'layouts/analytics' %>
    <%= javascript_include_tag :govuk_frontend, :type => "module" %>
    <%= javascript_include_tag :application %>
  </body>
</html>