fix: Ticker::then

app/util/promise.js

@@ -65,4 +65,10 @@ export class Ticker extends Promise {
     this.ticker(elapsed, this.resolve, this.reject);
   }
 
+  then(...args) {
+    const promise = super.then(...args);
+    promise.ticker = this.ticker;
+    return promise;
+  }
+
 }