fix chart off
diff --git a/src/editor/Preview.vue b/src/editor/Preview.vue
index 7f633e8..a8a408f 100644
--- a/src/editor/Preview.vue
+++ b/src/editor/Preview.vue
@@ -385,6 +385,7 @@
     // debouncedRun will be created at first run
     // debouncedRun: null,
     refreshAll() {
+      // PENDING full reload?
       this.run(true);
     },
     dispose() {
diff --git a/src/editor/sandbox/setup.js b/src/editor/sandbox/setup.js
index 1455f22..63480b2 100644
--- a/src/editor/sandbox/setup.js
+++ b/src/editor/sandbox/setup.js
@@ -56,7 +56,7 @@
   }
 
   function clearChartEvents(chart) {
-    chart && chartEvents.forEach(chart.off);
+    chart && chartEvents.forEach(chart.off.bind(chart));
     chartEvents.length = 0;
   }