navbar.html

<nav id="header_bar" class="navbar sticky-top navbar-expand-lg navbar-dark">
  <div class="container-fluid">
    <a class="navbar-brand short" href="{{ site.url }}"><i class="fas fa-home"></i>&nbsp;{{site.name_short}}</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarSupportedContent">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
      {%- for menu in site.data.topnavigation -%}
        {%- if menu.nav_items -%}
          {%- assign nav_items = menu.nav_items -%}
          {%- assign linkclass = "dropdown-item" -%}
          <li class="nav-item dropdown">
            <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown-{{menu.groupId}}" role="button" data-bs-toggle="dropdown" aria-haspopup="true" aria-expanded="false">{{ menu.title }}</a>
            <ul class="dropdown-menu" aria-labelledby="navbarDropdown-{{menu.groupId}}">
        {%- else -%}
          {%- assign nav_items = "" | split: "," -%}
          {%- assign nav_items = nav_items | push: menu -%}
          {%- assign linkclass = "nav-link" -%}
          {%- assign listclass = "nav-item" -%}
        {%- endif -%}
        {%- for item in nav_items -%}
          {%- include common/navbar_item.html item=item -%}
          {%- for subitem in item.nav_items -%}
            {%- include common/navbar_item.html item=subitem itemclass="sublevel" -%}
          {%- endfor -%}
        {%- endfor -%}
        {%- if menu.nav_items -%}
            </ul>
          </li>
        {%- endif -%}
      {%- endfor -%}
      </ul>
      <div class="d-flex">
        <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link" href="https://github.com/{{ site.repository }}/"><i class="fab fa-github"></i>&nbsp;GitHub</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="https://ym.fi/ryhti">Ryhti-hanke</a>
        </li>
        </ul>
      </div>
    </div>
  </div>
</nav>