diff --git a/layout/printing/nsPagePrintTimer.h b/layout/printing/nsPagePrintTimer.h
index 25b4a49e3a62..e0990dd4f89c 100644
--- a/layout/printing/nsPagePrintTimer.h
+++ b/layout/printing/nsPagePrintTimer.h
@@ -55,7 +55,11 @@ public:
   void WaitForRemotePrint();
   void RemotePrintFinished();
 
-  void Disconnect() { mPrintEngine = nullptr; }
+  void Disconnect()
+  {
+    mPrintEngine = nullptr;
+    mPrintObj = nullptr;
+  }
 
 private:
   ~nsPagePrintTimer();