Update schedule.js

Author: Roschool

schedule.js

@@ -1012,9 +1012,7 @@ async function showLessonInfo(lessonHTML, lesson) {
   if (!lesson.content) {
     lesson.content = "";
   }
-  let warning = [lesson.changeDescription, lesson.schedulerRemark, lesson.content]
-  .map(x => String(x || "").replace(/NaN/g, ""))
-  .join("");
+  let warning = lesson.changeDescription + lesson.schedulerRemark + lesson.content;
 
   if (lesson.cancelled == true) {
     lesson.appointmentType = "cancelled";