Fix

assets/index.njk

@@ -0,0 +1,10 @@
+{% extends "base.njk" %}
+{% block body_class %}browsing{% endblock %}
+{# Already on the index, so the nav entry marks the current page instead of
+   offering a link to it. #}
+{% block navbar_nav %}
+        <li class="nav-item">
+          <a class="nav-link active" aria-current="page" href="index.html">All books</a>
+        </li>
+{% endblock %}
+{% block content %}{{ content | safe }}{% endblock %}