test_app/public/phpMyAdmin4.8.5/templates/table/structure/add_column.twig

<form method="post" action="tbl_addfield.php" id="addColumns" name="addColumns">
    {{ Url_getHiddenInputs(db, table) }}
    {% if Util_showIcons('ActionLinksMode') %}
        {{ Util_getImage('b_insrow', 'Add column'|trans) }}&nbsp;
    {% endif %}
    {% set num_fields -%}
        <input type="number" name="num_fields" value="1" onfocus="this.select()" min="1" required />
    {%- endset %}
    {{ 'Add %s column(s)'|trans|format(num_fields)|raw }}
    <input type="hidden" name="field_where" value="after"/>&nbsp;
    {# I tried displaying the drop-down inside the label but with Firefox the drop-down was blinking #}
    <select name="after_field">
        <option value="first" data-pos="first">
            {% trans 'at beginning of table' %}
        </option>
        {% for one_column_name in columns_list %}
            <option value="{{ one_column_name }}"
                {{- loop.revindex0 == 0 ? ' selected="selected"' }}>
                {{ 'after %s'|trans|format(one_column_name|e) }}
            </option>
        {% endfor %}
    </select>
    <input type="submit" value="{% trans 'Go' %}" />
</form>