diff --git a/mozilla/layout/generic/nsObjectFrame.cpp b/mozilla/layout/generic/nsObjectFrame.cpp
index 06630a91f12..bec70e604ab 100644
--- a/mozilla/layout/generic/nsObjectFrame.cpp
+++ b/mozilla/layout/generic/nsObjectFrame.cpp
@@ -1598,7 +1598,7 @@ nsPluginInstanceOwner::~nsPluginInstanceOwner()
   {
     if (mPluginHost)
       mPluginHost->StopPluginInstance(mInstance);
-    NS_RELEASE(mInstance);
+    NS_IF_RELEASE(mInstance);
   }
 
   NS_IF_RELEASE(mPluginHost);
diff --git a/mozilla/layout/html/base/src/nsObjectFrame.cpp b/mozilla/layout/html/base/src/nsObjectFrame.cpp
index 06630a91f12..bec70e604ab 100644
--- a/mozilla/layout/html/base/src/nsObjectFrame.cpp
+++ b/mozilla/layout/html/base/src/nsObjectFrame.cpp
@@ -1598,7 +1598,7 @@ nsPluginInstanceOwner::~nsPluginInstanceOwner()
   {
     if (mPluginHost)
       mPluginHost->StopPluginInstance(mInstance);
-    NS_RELEASE(mInstance);
+    NS_IF_RELEASE(mInstance);
   }
 
   NS_IF_RELEASE(mPluginHost);