Fixed endless error

Handled the error if user input is undefined or just an empty string (which causes an endless error)

random-choice-picker/script.js

@@ -33,12 +33,14 @@ function randomSelect() {
 
     const interval = setInterval(() => {
         const randomTag = pickRandomTag()
-
+	
+	if (randomTag !== undefined) {
         highlightTag(randomTag)
 
         setTimeout(() => {
             unHighlightTag(randomTag)
         }, 100)
+	}
     }, 100);
 
     setTimeout(() => {
@@ -64,4 +66,4 @@ function highlightTag(tag) {
 
 function unHighlightTag(tag) {
     tag.classList.remove('highlight')
-}
+}