diff --git a/toolkit/components/extensions/test/mochitest/mochitest.ini b/toolkit/components/extensions/test/mochitest/mochitest.ini
index 970cc5e56901..4ffee19aeb35 100644
--- a/toolkit/components/extensions/test/mochitest/mochitest.ini
+++ b/toolkit/components/extensions/test/mochitest/mochitest.ini
@@ -1,5 +1,5 @@
 [DEFAULT]
-skip-if = os == 'android' || buildapp == 'b2g' || os == 'mac'
+skip-if = os == 'android' || buildapp == 'b2g' || buildapp == 'mulet' || os == 'mac'
 support-files =
   file_WebRequest_page1.html
   file_WebRequest_page2.html