4 window.existingCustomProperty = 1;
5 window.__proto__.windowPrototypeCustomProperty = 1;
6 window.Object.prototype.objectPrototypeCustomProperty = 1;
7 window.location.customProperty = 1;
8 window.history.customProperty = 1;
10 window.onload = function()
12 window.parent.postMessage('start', '*');
17 <iframe name="testiframe" src="data:text/html,<p>test iframe</p>"></iframe>
18 <img name="testimage" src="data:image/jpg,">