--- a/browser/extensions/formautofill/FormAutofillHandler.jsm
+++ b/browser/extensions/formautofill/FormAutofillHandler.jsm
@@ -80,35 +80,29 @@ FormAutofillHandler.prototype = {
                                       f.addressType == info.addressType &&
                                       f.contactType == info.contactType &&
                                       f.fieldName == info.fieldName)) {
         // A field with the same identifier already exists.
         log.debug("Not collecting a field matching another with the same info:", info);
         return null;
       }
 
-      let inputFormat = {
+      let formatWithElement = {
         section: info.section,
         addressType: info.addressType,
         contactType: info.contactType,
         fieldName: info.fieldName,
+        state: null,
+        element,
       };
-      // Clone the inputFormat for caching the fields and elements together
-      let formatWithElement = Object.assign({}, inputFormat);
 
-      inputFormat.index = autofillData.length;
-      autofillData.push(inputFormat);
-
-      formatWithElement.element = element;
       this.fieldDetails.push(formatWithElement);
     }
 
-    log.debug("Collected details on", autofillData.length, "fields");
-
-    return autofillData;
+    log.debug("Collected details on", this.fieldDetails.length, "fields");
   },
 
   /**
    * Processes form fields that can be autofilled, and populates them with the
    * data provided by backend.
    *
    * @param {Array<Object>} autofillResult
    *        Data returned by the user interface.