diff --git a/mozilla/browser/components/nsBrowserContentHandler.js b/mozilla/browser/components/nsBrowserContentHandler.js
index 427d54a5bfd..f114bb43629 100644
--- a/mozilla/browser/components/nsBrowserContentHandler.js
+++ b/mozilla/browser/components/nsBrowserContentHandler.js
@@ -339,6 +339,8 @@ var nsBrowserContentHandler = {
       openPreferences();
       cmdLine.preventDefault = true;
     }
+    if (cmdLine.handleFlag("silent", false))
+      cmdLine.preventDefault = true;
   },
 
   helpInfo : "  -browser            Open a browser window.\n",