diff --git a/toolkit/xre/nsAppRunner.cpp b/toolkit/xre/nsAppRunner.cpp
index 5bdefd13630..9d5d17e171c 100644
--- a/toolkit/xre/nsAppRunner.cpp
+++ b/toolkit/xre/nsAppRunner.cpp
@@ -688,51 +688,6 @@ SetUpSandboxEnvironment()
   }
 }
 
-#if defined(NIGHTLY_BUILD)
-static void
-CleanUpOldSandboxEnvironment()
-{
-  // Temporary code to clean up the old low integrity temp directories.
-  // The removal of this is tracked by bug 1165818.
-  nsCOMPtr<nsIFile> lowIntegrityMozilla;
-  nsresult rv = NS_GetSpecialDirectory(NS_WIN_LOW_INTEGRITY_TEMP_BASE,
-                              getter_AddRefs(lowIntegrityMozilla));
-  if (NS_WARN_IF(NS_FAILED(rv))) {
-    return;
-  }
-
-  nsCOMPtr<nsISimpleEnumerator> iter;
-  rv = lowIntegrityMozilla->GetDirectoryEntries(getter_AddRefs(iter));
-  if (NS_WARN_IF(NS_FAILED(rv))) {
-    return;
-  }
-
-  bool more;
-  nsCOMPtr<nsISupports> elem;
-  while (NS_SUCCEEDED(iter->HasMoreElements(&more)) && more) {
-    rv = iter->GetNext(getter_AddRefs(elem));
-    if (NS_FAILED(rv)) {
-      break;
-    }
-
-    nsCOMPtr<nsIFile> file = do_QueryInterface(elem);
-    if (!file) {
-      continue;
-    }
-
-    nsAutoString leafName;
-    rv = file->GetLeafName(leafName);
-    if (NS_FAILED(rv)) {
-      continue;
-    }
-
-    if (leafName.Find(NS_LITERAL_STRING("MozTemp-{")) == 0) {
-      file->Remove(/* aRecursive */ true);
-    }
-  }
-}
-#endif
-
 static void
 CleanUpSandboxEnvironment()
 {
@@ -741,10 +696,6 @@ CleanUpSandboxEnvironment()
     return;
   }
 
-#if defined(NIGHTLY_BUILD)
-  CleanUpOldSandboxEnvironment();
-#endif
-
   // Get temp directory suffix pref.
   nsAdoptingString tempDirSuffix =
     Preferences::GetString("security.sandbox.content.tempDirSuffix");