Chrome Version: 61.0.3136.5
OS: Chromebook Nyan-blaze

What steps will reproduce the problem?
(1) navigate to https://www.youtube.com/watch?v=52zmpRT5RFg
(2) change resolution to 1440p or 2160p
when change resolution to 1080p, playback becomes smooth and low drop rate.

What is the expected result?
reasonable frame drop rate, no stutter in playback

What happens instead?
30% drop rate, obvious stutter