diff --git a/browser_patches/firefox/BUILD_NUMBER b/browser_patches/firefox/BUILD_NUMBER
index b800a0ea81..4133844557 100644
--- a/browser_patches/firefox/BUILD_NUMBER
+++ b/browser_patches/firefox/BUILD_NUMBER
@@ -1,2 +1,2 @@
-1165
-Changed: yurys@chromium.org Thu Aug 20 13:05:37 PDT 2020
+1166
+Changed: yurys@chromium.org Thu Aug 20 13:55:50 PDT 2020
diff --git a/browser_patches/firefox/juggler/protocol/BrowserHandler.js b/browser_patches/firefox/juggler/protocol/BrowserHandler.js
index 63908ecf1e..f5d0e087eb 100644
--- a/browser_patches/firefox/juggler/protocol/BrowserHandler.js
+++ b/browser_patches/firefox/juggler/protocol/BrowserHandler.js
@@ -33,13 +33,13 @@ class BrowserHandler {
       if (!this._shouldAttachToTarget(target))
         continue;
       const session = this._dispatcher.createSession();
-      target.initSession(session);
-      target.connectSession(session);
       this._attachedSessions.set(target, session);
       this._session.emitEvent('Browser.attachedToTarget', {
         sessionId: session.sessionId(),
         targetInfo: target.info()
       });
+      target.initSession(session);
+      target.connectSession(session);
     }
 
     this._eventListeners = [
@@ -92,12 +92,12 @@ class BrowserHandler {
     if (!this._shouldAttachToTarget(target))
       return;
     const session = this._dispatcher.createSession();
-    target.initSession(session);
     this._attachedSessions.set(target, session);
     this._session.emitEvent('Browser.attachedToTarget', {
       sessionId: session.sessionId(),
       targetInfo: target.info()
     });
+    target.initSession(session);
     sessions.push(session);
   }