Unable to copy RTC workitem description using javascript

I created a calculated Value with the below script based on yours and set  it to a custom attribute: medium string or HTML and this works for me:

dojo.provide("com.example.common.MyClass");

dojo.require("com.ibm.team.workitem.api.common.WorkItemAttributes");
(function() {
var WorkItemAttributes= com.ibm.team.workitem.api.common.WorkItemAttributes;
dojo.declare("com.example.common.MyClass", null, {

    getValue: function(attributeId, workItem, configuration) {

        var value =  workItem.getValue(WorkItemAttributes.DESCRIPTION); 
   
         return value;

    }
});

})();