diff --git a/.eslintrc.tests.json b/.eslintrc.tests.json
index 9a39bae2a1..081ab41709 100644
--- a/.eslintrc.tests.json
+++ b/.eslintrc.tests.json
@@ -11,7 +11,6 @@
     // Exceptions
     "func-names": 0,
     // To add
-    "no-bitwise": 0,
     "max-len": 0,
     "no-underscore-dangle": 0,
     "no-shadow": 0,
diff --git a/tests/javascript/mochaTestHelper.js b/tests/javascript/mochaTestHelper.js
index b78353a046..55c038a32b 100644
--- a/tests/javascript/mochaTestHelper.js
+++ b/tests/javascript/mochaTestHelper.js
@@ -23,9 +23,6 @@ if (!global.document || !global.window) {
   global.window = document.parentWindow;
   global.navigator = global.window.navigator;
 
-  global.window.Node.prototype.contains = function (node) {
-    return this.compareDocumentPosition(node) & 16;
-  };
 }
 const testHelpers = require('./loadHelpers.js');
 global.testHelpers = testHelpers;