diff --git a/xul/content/static.js b/xul/content/static.js
--- a/xul/content/static.js
+++ b/xul/content/static.js
@@ -2339,17 +2339,17 @@ client.idleObserver = {
     {
         if ((topic == "idle") && !client.prefs["away"])
         {
             if (!client.prefs["awayIdleMsg"])
                 client.prefs["awayIdleMsg"] = MSG_AWAY_IDLE_DEFAULT;
             client.dispatch("idle-away", {reason: client.prefs["awayIdleMsg"]});
             client.isIdleAway = true;
         }
-        else if ((topic == "back") && client.isIdleAway)
+        else if ((topic == "back" || topic == "active") && client.isIdleAway)
         {
             client.dispatch("idle-back");
             client.isIdleAway = false;
         }
     }
 };
 
 function initIdleAutoAway(timeout)