Bootstrap3多选字段-两次选择一个ID

Question

我想要一个多重选择框，它能够两次选择一个ID /值。因此用户可以添加多个具有相同值/ id的项目

<select class="panels form-control select2-taggable select2-hidden-accessible" name="panels[]" multiple=""
  tabindex="-1" aria-hidden="true">
  @foreach( $products->filter( function($value, $key){ if($value["product_category_id"] == 11) { return true; } } ) as $product )
    <option value="{{ $product->id }}" {{ $room->products->firstWhere("product_id", $product->id ) ? 'selected' : '' }} >{{ $product->title }}</option>
  @endforeach
  </select>