diff --git a/chrome/ScreenSharing/background-script.js b/chrome/ScreenSharing/background-script.js
index 2c8b6a8..ecff13d 100644
--- a/chrome/ScreenSharing/background-script.js
+++ b/chrome/ScreenSharing/background-script.js
@@ -1,7 +1,7 @@
 // this background script is used to invoke desktopCapture API
 // to capture screen-MediaStream.
 
-var session = ['screen', 'window'];
+var session = ['screen', 'window', 'tab'];
 
 function getSourceID(sender, callback) {
   // as related in https://code.google.com/p/chromium/issues/detail?id=413602 and https://code.google.com/p/chromium/issues/detail?id=425344 :