diff --git a/README.md b/README.md
index 5477b75..473eb4f 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,5 @@
+I've tried to add blocking for groups, however have not testet it yet.
+
 # Unseen extension for Firefox
 
 ![Screenshot of Facebook's 'seen' status](http://i45.tinypic.com/2yv44r7.png)
diff --git a/src/bootstrap.js b/src/bootstrap.js
index fcd3aae..cc73e5b 100644
--- a/src/bootstrap.js
+++ b/src/bootstrap.js
@@ -13,13 +13,14 @@ function httpObserve() {
 httpObserve.prototype = {
     registerTopic:      "http-on-modify-request",
     facebookReadStatusUrl: /http(s)?:\/\/(www.)?facebook.com\/ajax\/mercury\/change_read_status.php(\?(.)+)?/,
+    facebookGroupStatusUrl : /http(s)?:\/\/(www.)?facebook.com\/ajax\/ufi\/seen_tooltip.php(\?(.)+)?/,
 
     observe: function(subject, topic, data) {
         if (topic == this.registerTopic) {
             subject.QueryInterface(Components.interfaces.nsIHttpChannel);
             var url = subject.URI.spec;
 
-            if (this.facebookReadStatusUrl.test(url)) {
+            if (this.facebookReadStatusUrl.test(url) || this.facebookGroupStatusUrl.test(url)) {
                 subject.cancel(Components.results.NS_BINDING_ABORTED);
             }
         }
@@ -45,4 +46,4 @@ function startup(data, reason) {
 function shutdown(data, reason) {
     obs.unregister();
     obs = null;
-}
\ No newline at end of file
+}