<!-- Two top-level blocks with the same name (the issue's example) -->
{% block title %}Title 1{% endblock %}
{% block title %}Title 2{% endblock %}

<!-- Three occurrences of one name report two diagnostics -->
{% block header %}a{% endblock %}
{% block header %}b{% endblock %}
{% block header %}c{% endblock %}

<!-- A block nested inside another block of the same name -->
{% block content %}
    {% block content %}inner{% endblock %}
{% endblock %}

<!-- The same name in different {% if %} branches still counts (Django registers both) -->
{% if cond %}
    {% block sidebar %}on{% endblock %}
{% else %}
    {% block sidebar %}off{% endblock %}
{% endif %}