  assert_equals(target.offsetLeft, 300);
    cb.classList.add('shrink');
    target.classList.add('fallback', 'anim');
    // Now we take the --200 fallback:
    assert_equals(target.offsetLeft, 250);
  }, 'Transition when @position-try is applied');

  test((t) => {
    t.add_cleanup(cleanup);
    cb.classList.add('shrink');
    target.classList.add('fallback');
    assert_equals(target.offsetLeft, 200);
    cb.classList.remove('shrink');
    target.classList.remove('fallback');
    target.classList.add('a