main.html

{% extends "base.html" %}

{% block announce %}
<label for="version">Version</label>
<select style="margin-left:8px;" id="version" name="version" onchange="switchVersion(this.options[this.selectedIndex].value)">
    <option value="latest">latest</option>
    <option value="1.4.1">1.4.1</option>
    <option value="1.4.0">1.4.0</option>
    <option value="1.3.0">1.3.0</option>
</select>
{% endblock %}