U4-7239 Now trims the parameters so that if a default is set in a comma and space seperated list, the parameter is now populated.

src/Umbraco.Web/umbraco.presentation/helper.cs

@@ -95,12 +95,14 @@ namespace umbraco
             {
                 var attributeValueSplit = (attributeValue).Split(',');
 
+                attributeValueSplit = attributeValueSplit.Select(x => x.Trim()).ToArray();
+
                 // before proceeding, we don't want to process anything here unless each item starts/ends with a [ ]
                 // this is because the attribute value could actually just be a json array like [1,2,3] which we don't want to parse
                 //
                 // however, the last one can be a literal, must take care of this!
                 // so here, don't check the last one, which can be just anything
-                if (attributeValueSplit.Take(attributeValueSplit.Length - 1).All(x =>
+                if (attributeValueSplit.Take(attributeValueSplit.Length - 1).All(x => 
                     //must end with [
                     x.EndsWith("]") &&
                     //must start with [ and a special char