diff --git a/toolkit/mozapps/extensions/test/browser/browser.ini b/toolkit/mozapps/extensions/test/browser/browser.ini
index 1b999e66fec2..e4bf0e7f433d 100644
--- a/toolkit/mozapps/extensions/test/browser/browser.ini
+++ b/toolkit/mozapps/extensions/test/browser/browser.ini
@@ -9,6 +9,7 @@ support-files =
   discovery.html
   discovery_frame.html
   discovery_install.html
+  head.js
   signed_hotfix.rdf
   signed_hotfix.xpi
   unsigned_hotfix.rdf