Skipping answer simplification if value is undefined

src/utils/classes.js

@@ -146,6 +146,9 @@ function simplifyQA(value, mods) {
 }
 
 function simplifyAnswer(value) {
+  if (!value) {
+    return value
+  }
   return simplifyQA(value, [
     removeSpecialChars,
     removeUnnecesarySpaces,