This page tests what happens when a getter / setter on the window object conflicts with another property or declared variable On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS window.x is 1 PASS typeof window.__lookupGetter__('x') is 'undefined' PASS typeof Object.getOwnPropertyDescriptor(window, 'x').get is 'undefined' PASS window.x is 2 PASS typeof window.__lookupGetter__('x') is 'undefined' PASS typeof Object.getOwnPropertyDescriptor(window, 'x').get is 'undefined' PASS window.y is 'window.y __getter__' PASS typeof window.__lookupGetter__('y') is 'function' PASS typeof Object.getOwnPropertyDescriptor(window, 'y').get is 'function' PASS window.y is 'window.y __getter__' PASS typeof window.__lookupGetter__('y') is 'function' PASS typeof Object.getOwnPropertyDescriptor(window, 'y').get is 'function' PASS window.z is undefined. PASS typeof window.__lookupSetter__('z') is 'function' PASS typeof Object.getOwnPropertyDescriptor(window, 'z').set is 'function' PASS successfullyParsed is true TEST COMPLETE