Follow track change when toggle

ui/src/lib/track.js

@@ -24,10 +24,9 @@ export class Track {
     }
   }
 
-  toggleEnable() {
+  async toggleEnable() {
     this.enabled = !this.enabled;
-    this.save();
-    return this;
+    return await this.save();
   }
 
   async save() {
@@ -39,7 +38,7 @@ export class Track {
     if (res.status == 200) {
       const data = await res.json();
       this.update(data);
-      return data;
+      return this;
     } else {
       throw new Error((await res.json()).errmsg);
     }