diff --git a/index.d.ts b/index.d.ts
index 2a628ade..4af6fc99 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -4,3 +4,26 @@ declare namespace mitt {
     (all?: { [key: string]: Array<Handler> }): Emitter;
   }
 }
+
+declare module 'delegated-events' {
+  type EventHandler = (event: Event) => any;
+
+  type EventListenerOptions = {
+    capture?: boolean;
+    document?: Document;
+  };
+
+  export function on(
+    name: string,
+    selector: string,
+    handler: EventHandler,
+    options?: EventListenerOptions,
+  ): void;
+  export function off(
+    name: string,
+    selector: string,
+    handler: EventHandler,
+    options?: EventListenerOptions,
+  ): void;
+  export function fire(target: EventTarget, name: string, detail?: any): void;
+}
diff --git a/package.json b/package.json
index 1dc77585..9212c64c 100644
--- a/package.json
+++ b/package.json
@@ -53,6 +53,7 @@
     "typescript": "^3.1.6"
   },
   "dependencies": {
+    "delegated-events": "git+https://git@github.com/rrweb-io/delegated-events.git",
     "mitt": "^1.1.3",
     "rrweb-snapshot": "^0.6.1"
   }
diff --git a/src/record/index.ts b/src/record/index.ts
index 9076d168..b886607f 100644
--- a/src/record/index.ts
+++ b/src/record/index.ts
@@ -53,8 +53,8 @@ function record(options: recordOptions = {}) {
           data: {
             node,
             initialOffset: {
-              left: document.documentElement.scrollLeft,
-              top: document.documentElement.scrollTop,
+              left: document.documentElement!.scrollLeft,
+              top: document.documentElement!.scrollTop,
             },
           },
         }),
diff --git a/src/replay/index.ts b/src/replay/index.ts
index 9588734a..9f9dac2a 100644
--- a/src/replay/index.ts
+++ b/src/replay/index.ts
@@ -1,5 +1,6 @@
 import { rebuild, buildNodeWithSN } from 'rrweb-snapshot';
 import * as mittProxy from 'mitt';
+import { on, off } from 'delegated-events';
 import Timer from './timer';
 import {
   EventType,
@@ -155,7 +156,7 @@ export class Replayer {
       const firstOffset = event.data.positions[0].timeOffset;
       // timeOffset is a negative offset to event.timestamp
       const firstTimestamp = event.timestamp + firstOffset;
-      const delay = firstTimestamp - this.baselineTime
+      const delay = firstTimestamp - this.baselineTime;
       event.data.positions = event.data.positions.map(p => {
         return {
           ...p,
@@ -207,17 +208,23 @@ export class Replayer {
   ) {
     mirror.map = rebuild(event.data.node, this.iframe.contentDocument!)[1];
     // avoid form submit to refresh the iframe
-    this.iframe.contentDocument!.addEventListener('submit', evt => {
-      if (evt.target && (evt.target as Element).tagName === 'FORM') {
-        evt.preventDefault();
-      }
+    off('submit', 'form', this.preventDefault, {
+      document: this.iframe.contentDocument!,
+    });
+    on('submit', 'form', this.preventDefault, {
+      document: this.iframe.contentDocument!,
     });
     // avoid a link click to refresh the iframe
-    this.iframe.contentDocument!.addEventListener('click', evt => {
-      if (evt.target && (evt.target as Element).tagName === 'A') {
-        evt.preventDefault();
-      }
+    off('click', 'a', this.preventDefault, {
+      document: this.iframe.contentDocument!,
     });
+    on('click', 'a', this.preventDefault, {
+      document: this.iframe.contentDocument!,
+    });
+  }
+
+  private preventDefault(evt: Event) {
+    evt.preventDefault();
   }
 
   private applyIncremental(d: incrementalData, isSync: boolean) {