diff --git a/app/scripts/lib/notification-manager.js b/app/scripts/lib/notification-manager.js
index 5dfb42078..6b88a7a99 100644
--- a/app/scripts/lib/notification-manager.js
+++ b/app/scripts/lib/notification-manager.js
@@ -32,6 +32,8 @@ class NotificationManager {
           type: 'popup',
           width,
           height,
+        }).then((currentPopup) => {
+          this._popupId = currentPopup.id
         })
       }
     })
@@ -84,7 +86,7 @@ class NotificationManager {
   }
 
   /**
-   * Given an array of windows, returns the first that has a 'popup' type, or null if no such window exists.
+   * Given an array of windows, returns the 'popup' that has been opened by MetaMask, or null if no such window exists.
    *
    * @private
    * @param {array} windows An array of objects containing data about the open MetaMask extension windows.
@@ -93,7 +95,7 @@ class NotificationManager {
   _getPopupIn (windows) {
     return windows ? windows.find((win) => {
       // Returns notification popup
-      return (win && win.type === 'popup')
+      return (win && win.type === 'popup' && win.id === this._popupId)
     }) : null
   }