diff --git a/dom/xbl/test/mochitest.ini b/dom/xbl/test/mochitest.ini
index a37b7437e3b..67041433866 100644
--- a/dom/xbl/test/mochitest.ini
+++ b/dom/xbl/test/mochitest.ini
@@ -37,6 +37,7 @@ skip-if = (buildapp == 'b2g' && toolkit != 'gonk') #Bug 931116, b2g desktop spec
 [test_bug639338.xhtml]
 [test_bug790265.xhtml]
 [test_bug821850.html]
+skip-if = buildapp == 'mulet'
 [test_bug844783.html]
 [test_bug872273.xhtml]
 [test_bug946815.html]
diff --git a/embedding/test/mochitest.ini b/embedding/test/mochitest.ini
index 897fc6db196..bc1df2ae830 100644
--- a/embedding/test/mochitest.ini
+++ b/embedding/test/mochitest.ini
@@ -9,6 +9,6 @@ support-files =
 [test_private_window_from_content.html]
 # Next two tests are disabled in e10s because of bug 989501.
 [test_window_open_position_constraint.html]
-skip-if = toolkit == 'android' || e10s
+skip-if = toolkit == 'android' || e10s || buildapp == 'mulet'
 [test_window_open_units.html]
-skip-if = toolkit == 'android' || e10s
+skip-if = toolkit == 'android' || e10s || buildapp == 'mulet'