diff --git a/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp b/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
index 7e3a7731f23..ecc577ecc29 100644
--- a/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
+++ b/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
@@ -596,6 +596,8 @@ NS_IMETHODIMP nsWebBrowser::SetProperty(PRUint32 aId, PRUint32 aValue)
            NS_ENSURE_TRUE((aValue == PR_TRUE || aValue == PR_FALSE), NS_ERROR_INVALID_ARG);
            mDocShell->SetAllowPlugins(aValue);
         }
+        break;
+
     default:
         return NS_ERROR_INVALID_ARG;