| <!DOCTYPE html> | |
| <title id="t"></title> | |
| <script src="../resources/testharness.js"></script> | |
| <script src="../resources/testharnessreport.js"></script> | |
| <script src="spec/resources/custom-elements-helpers.js"></script> | |
| <body id="b"> | |
| <script> | |
| test_with_window((w) => { | |
| class X extends w.HTMLElement {} | |
| t.appendChild(b); | |
| // If the following line does not crash, the test passed. | |
| w.customElements.define('a-a', X); | |
| }); | |
| </script> |