Made the partials explicit in their section (i.e. user)

templates/forms/partials/input-user-group.html.twig

@@ -0,0 +1,21 @@
+{% block input_user_group %}
+{% if 'group' not in form.fields.hidden %}
+<div class="form-group">
+    <label for="input-user-group">{{translate('GROUP')}}</label>
+    <div class="input-group">
+        <span class="input-group-addon"><i class="fas fa-users fa-fw"></i></span>
+        {% if 'group' in form.fields.disabled %}
+            <input type="text" class="form-control" name="theme" value="{{user.group.name}}" disabled>
+        {% else %}
+            <select id="input-user-group" class="form-control js-select2" name="group_id">
+                <option value="0">{{translate('GROUP.NONE')}}</option>
+                <option disabled="disabled">-----</option>
+                {% for group in groups %}
+                <option value="{{group.id}}" {% if (group.id == user.group_id) %}selected{% endif %}>{{group.name}}</option>
+                {% endfor %}
+            </select>
+        {% endif %}
+    </div>
+</div>
+{% endif %}
+{% endblock %}