_includes/version-select.html

{% if page.version %}
<div class="dropdown pt-3 has-text-left">
    <div class="dropdown-trigger">
        <button class="button" aria-haspopup="true" aria-controls="dropdown-menu3">
            <span>{{ page.version }}</span>
            <span class="icon is-small">
                <i class="fas fa-angle-down" aria-hidden="true"></i>
            </span>
        </button>
    </div>
    <div class="dropdown-menu">
        <div class="dropdown-content">
            {% for ver in site.pegasus_versions %}

            <!--URL of our latest version always starts without version prefixed.-->
            {% assign version_prefix = page.version | append: '/' %}
            {% assign no_version_link = page.permalink | remove_first: version_prefix %}
            {% if ver == site.latest_pegasus_version %}
            {% assign version_url = no_version_link %}
            {% else %}
            {% assign version_url = '/' | append: ver | append: '/' | append: no_version_link %}
            {% endif %}

            <a href="{{ version_url }}" class="dropdown-item {% if ver == page.version %}is-active{% endif %}">
                {{ ver }}
            </a>
            {% endfor %}
        </div>
    </div>
</div>
{% endif %}