notifications-admin/app/templates/error/500.html

{% extends "withoutnav_template.html" %}
{% block page_title %}Server error{% endblock %}
{% block maincolumn_content %}
  <div class="grid-row">
    <div class="column-two-thirds">
      <h1 class="heading-large">
        Sorry, we’re experiencing technical difficulties
      </h1>
      <p>Try again later.</p>
    </div>
  </div>
{% endblock %}