Interactive controls are not available in the static export.
{% props items = ['a', 'b'], shouted = 'x'|upper %}
<ul class="teaser" data-shouted="{{ shouted }}">
{% for item in items %}
<li>{{ item }}</li>
{% endfor %}
</ul>
<ul class="teaser" data-shouted="X">
<li>a</li>
<li>b</li>
</ul>
<twig:Teaser>
</twig:Teaser>