diff --git a/mozilla/webshell/tests/viewer/unix/gtk/nsGtkMain.cpp b/mozilla/webshell/tests/viewer/unix/gtk/nsGtkMain.cpp
index 8490e0b3aa4..cfbbaebd973 100644
--- a/mozilla/webshell/tests/viewer/unix/gtk/nsGtkMain.cpp
+++ b/mozilla/webshell/tests/viewer/unix/gtk/nsGtkMain.cpp
@@ -46,7 +46,9 @@ int
 nsNativeViewerApp::Run()
 {
   OpenWindow();
+  NS_ADDREF(mAppShell);
   mAppShell->Run();
+  NS_IF_RELEASE(mAppShell);
   return 0;
 }