portainer/app/docker/components/host-view-panels/node-availability-select/node-availability-select.html

<div class="input-group input-group-sm">
  <select name="nodeAvailability" class="selectpicker form-control" ng-model="$ctrl.availability"
    ng-change="$ctrl.onChange($event)">
    <option value="active">Active</option>
    <option value="pause">Pause</option>
    <option value="drain">Drain</option>
  </select>
  <div class="btn-toolbar" role="toolbar">
    <div class="btn-group" role="group">
      <button type="button" class="btn btn-primary btn-sm" ng-disabled="!$ctrl.state.hasChanges"
        ng-click="$ctrl.save()">Apply changes</button>
      <button type="button" class="btn btn-default btn-sm dropdown-toggle" data-toggle="dropdown"
        aria-haspopup="true" aria-expanded="false">
        <span class="caret"></span>
      </button>
      <ul class="dropdown-menu">
        <li><a ng-click="$ctrl.cancelChanges()">Reset changes</a></li>
      </ul>
    </div>
  </div>
</div>