diff --git a/uriloader/exthandler/nsExternalHelperAppService.cpp b/uriloader/exthandler/nsExternalHelperAppService.cpp
index c78569dedaa..c2c67b00a9b 100644
--- a/uriloader/exthandler/nsExternalHelperAppService.cpp
+++ b/uriloader/exthandler/nsExternalHelperAppService.cpp
@@ -923,7 +923,10 @@ NS_IMETHODIMP nsExternalHelperAppService::GetApplicationDescription(const nsACSt
 // Methods related to deleting temporary files on exit
 //////////////////////////////////////////////////////////////////////////////////////////////////////
 
-NS_IMETHODIMP nsExternalHelperAppService::DeleteTemporaryFileOnExit(nsIFile * aTemporaryFile)
+/* static */
+nsresult
+nsExternalHelperAppService::DeleteTemporaryFileHelper(nsIFile * aTemporaryFile,
+                                                      nsCOMArray<nsIFile> &aFileList)
 {
   bool isFile = false;
 
@@ -931,14 +934,23 @@ NS_IMETHODIMP nsExternalHelperAppService::DeleteTemporaryFileOnExit(nsIFile * aT
   aTemporaryFile->IsFile(&isFile);
   if (!isFile) return NS_OK;
 
-  if (mInPrivateBrowsing)
-    mTemporaryPrivateFilesList.AppendObject(aTemporaryFile);
-  else
-    mTemporaryFilesList.AppendObject(aTemporaryFile);
+  aFileList.AppendObject(aTemporaryFile);
 
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsExternalHelperAppService::DeleteTemporaryFileOnExit(nsIFile* aTemporaryFile)
+{
+  return DeleteTemporaryFileHelper(aTemporaryFile, mTemporaryFilesList);
+}
+
+NS_IMETHODIMP
+nsExternalHelperAppService::DeleteTemporaryPrivateFileWhenPossible(nsIFile* aTemporaryFile)
+{
+  return DeleteTemporaryFileHelper(aTemporaryFile, mTemporaryPrivateFilesList);
+}
+
 void nsExternalHelperAppService::FixFilePermissions(nsIFile* aFile)
 {
   // This space intentionally left blank
diff --git a/uriloader/exthandler/nsExternalHelperAppService.h b/uriloader/exthandler/nsExternalHelperAppService.h
index 59505ba43b3..3813479ccd3 100644
--- a/uriloader/exthandler/nsExternalHelperAppService.h
+++ b/uriloader/exthandler/nsExternalHelperAppService.h
@@ -172,6 +172,11 @@ protected:
    * Helper function for ExpungeTemporaryFiles and ExpungeTemporaryPrivateFiles
    */
   static void ExpungeTemporaryFilesHelper(nsCOMArray<nsIFile> &fileList);
+  /**
+   * Helper function for DeleteTemporaryFileOnExit and DeleteTemporaryPrivateFileWhenPossible
+   */
+  static nsresult DeleteTemporaryFileHelper(nsIFile* aTemporaryFile,
+                                            nsCOMArray<nsIFile> &aFileList);
   /**
    * Functions related to the tempory file cleanup service provided by
    * nsExternalHelperAppService
diff --git a/uriloader/exthandler/nsIExternalHelperAppService.idl b/uriloader/exthandler/nsIExternalHelperAppService.idl
index e5ee8b7549e..c0066ec31a3 100644
--- a/uriloader/exthandler/nsIExternalHelperAppService.idl
+++ b/uriloader/exthandler/nsIExternalHelperAppService.idl
@@ -53,7 +53,7 @@ interface nsIExternalHelperAppService : nsISupports
  * This is a private interface shared between external app handlers and the platform specific
  * external helper app service
  */
-[scriptable, uuid(d0b5d7d3-9565-403d-9fb5-e5089c4567c6)]
+[scriptable, uuid(6613e2e7-feab-4e3a-bb1f-b03200d544ec)]
 interface nsPIExternalAppLauncher : nsISupports
 {
   /**
@@ -62,6 +62,11 @@ interface nsPIExternalAppLauncher : nsISupports
    * @param aTemporaryFile A temporary file we should delete on exit.
    */
   void deleteTemporaryFileOnExit(in nsIFile aTemporaryFile); 
+  /**
+   * Delete a temporary file created inside private browsing mode when
+   * the private browsing mode has ended.
+   */
+  void deleteTemporaryPrivateFileWhenPossible(in nsIFile aTemporaryFile);
 };
 
 /**