Fix: Missing empty field

htdocs/core/class/extrafields.class.php

@@ -681,6 +681,7 @@ class ExtraFields
 			}
 
 			$out.='<select class="flat" name="options_'.$key.$keyprefix.'" id="options_'.$key.$keyprefix.'" '.($moreparam?$moreparam:'').'>';
+			$out.='<option value="0">&nbsp;</option>';
 			foreach ($param['options'] as $key=>$val )
 			{
 				list($val, $parent) = explode('|', $val);