The WPT test scroll-animations/scroll-timelines/reverse-animation.html has 3 failures: FAIL Reversing an animation resets a sticky start time. assert_approx_equals: values do not match for "undefined" expected 100 +/- 0.125 but got 40 FAIL Reversing when when playbackRate == 0 should preserve the playback rate assert_approx_equals: values do not match for "Anchors to range start boundary when playback rate is zero" expected 0 +/- 0.125 but got 50 FAIL Reversing an idle animation aligns startTime with the rangeEnd boundary assert_approx_equals: values do not match for "animation.startTime should be at its effect end" expected 100 +/- 0.125 but got -100