I was testing out a navbar in my Jekyll site and can’t get anything I write in the front matter to show up in it. Jekyll is showing no build errors.

I have a layout default.html, which I then include navigation.html in.
My navigation.html looks like this:

<div>
    {% if site.data.samplelist.toc2[0] %}
      {% for item in site.data.samplelist.toc2 %}
        <h3>{{ item.title }}</h3>
          {% if item.subfolderitems[0] %}
            <ul>
              {% for entry in item.subfolderitems %}
                  <li><a href="{{ entry.url }}">{{ entry.page }}</a>
                    {% if entry.subsubfolderitems[0] %}
                      <ul>
                      {% for subentry in entry.subsubfolderitems %}
                          <li><a href="{{ subentry.url }}">{{ subentry.page }}</a></li>
                      {% endfor %}
                      </ul>
                    {% endif %}
                  </li>
              {% endfor %}
            </ul>
          {% endif %}
        {% endfor %}
    {% endif %}
</div>

Here is the front matter of the page I’m testing:

---
layout: docs
title: "The Difference between は and が"
toc2:
  - title: Group 1
    subfolderitems:
      - page: Thing 1
        url: /thing1.html
      - page: Thing 2
        url: /thing2.html
        subsubfolderitems:
          - page: Subthing 1
            url: /subthing1.html
          - page: Subthing 2
            url: /subthing2.html
      - page: Thing 3
        url: /thing3.html
  - title: Group 2
    subfolderitems:
      - page: Piece 1
        url: /piece1.html
      - page: Piece 2
        url: /piece2.html
      - page: Piece 3
        url: /piece3.html
        subsubfolderitems:
          - page: Subpiece 1
            url: /subpiece1.html
          - page: Subpiece2
            url: /subpiece2.html
  - title: Group 3
    subfolderitems:
      - page: Widget 1
        url: /widget1.html
        subsubfolderitems:
          - page: Subwidget 1
            url: /subwidget1.html
          - page: Subwidget 2
            url: /subwidget2.html
      - page: Widget 2
        url: /widget2.html
      - page: Widget 3
        url: /widget3.html
---

The front matter is an example from the Jekyll doc website. But after I build nothing shows up in the navigation div.

Even if I do something simple like have food: Pizza in my front matter and then have <h1>{{ page.food }}</h1> on my default layout, nothing is returned. It only returns something if I paste <h1>{{ page.food }}</h1> on the .md page with the custom front matter directly.