This is a testharness.js-based test.
[FAIL] container > item 2
assert_equals: \n<item data-offset-x="58" class="collapsed"></item>\noffsetLeft expected 58 but got 108
[FAIL] container > item 3
assert_equals: \n<item data-offset-x="58" class="collapsed"></item>\noffsetLeft expected 58 but got 108
Harness: the test ran to completion.