diff --git a/devtools/server/tests/xpcshell/head_dbg.js b/devtools/server/tests/xpcshell/head_dbg.js
index b50d48254217..c338dddeb948 100644
--- a/devtools/server/tests/xpcshell/head_dbg.js
+++ b/devtools/server/tests/xpcshell/head_dbg.js
@@ -23,7 +23,7 @@ const { require, loader } = ChromeUtils.import(
 const { worker } = ChromeUtils.import(
   "resource://devtools/shared/worker/loader.js"
 );
-const defer = require("devtools/shared/defer");
+
 const { NetUtil } = require("resource://gre/modules/NetUtil.jsm");
 
 const Services = require("Services");