diff --git a/testing/web-platform/tests/html/webappapis/system-state-and-capabilities/the-navigator-object/NavigatorID.js b/testing/web-platform/tests/html/webappapis/system-state-and-capabilities/the-navigator-object/NavigatorID.js
index a7e8b1dba8e..50895316191 100644
--- a/testing/web-platform/tests/html/webappapis/system-state-and-capabilities/the-navigator-object/NavigatorID.js
+++ b/testing/web-platform/tests/html/webappapis/system-state-and-capabilities/the-navigator-object/NavigatorID.js
@@ -22,10 +22,6 @@ function run_test() {
     assert_equals(navigator.product, "Gecko");
   }, "product");
 
-  test(function() {
-    assert_false(navigator.taintEnabled());
-  }, "taintEnabled");
-
   test(function() {
     assert_equals(typeof navigator.userAgent, "string",
                   "navigator.userAgent should be a string");
diff --git a/testing/web-platform/tests/workers/interfaces.idl b/testing/web-platform/tests/workers/interfaces.idl
index 5bfd2883525..7b30ba56301 100644
--- a/testing/web-platform/tests/workers/interfaces.idl
+++ b/testing/web-platform/tests/workers/interfaces.idl
@@ -96,7 +96,6 @@ interface NavigatorID {
   readonly attribute DOMString appVersion;
   readonly attribute DOMString platform;
   readonly attribute DOMString product; // constant "Gecko"
-  boolean taintEnabled(); // constant false
   readonly attribute DOMString userAgent;
 };