diff --git a/toolkit/components/jsdownloads/src/DownloadUIHelper.jsm b/toolkit/components/jsdownloads/src/DownloadUIHelper.jsm
index 3039525f5f..a565dfa3a3 100644
--- a/toolkit/components/jsdownloads/src/DownloadUIHelper.jsm
+++ b/toolkit/components/jsdownloads/src/DownloadUIHelper.jsm
@@ -129,7 +129,7 @@ this.DownloadPrompter.prototype = {
    *
    * @resolves Boolean indicating whether the launch operation can continue.
    */
-  async confirmLaunchExecutable: function (aPath)
+  confirmLaunchExecutable: async function (aPath)
   {
     const kPrefConfirmOpenExe = "browser.download.confirmOpenExecutable";