This is a testharness.js-based test.
[FAIL] Make sure that relList based feature detection is working
Cannot read properties of undefined (reading 'contains')
Harness: the test ran to completion.
This is a testharness.js-based test.
[FAIL] Make sure that relList based feature detection is working
Cannot read properties of undefined (reading 'contains')
Harness: the test ran to completion.