Google apparently implemented a redesign on how YouTube works on browsers with the Polymer update, which relies on a Shadow DOM v0 API that’s only available in Google Chrome. This means that loading YouTube on other browsers that is not Chrome will result in it loading slower and ultimately affecting end-user playback.
Softpedia picked up the news from Mozilla programming manager and engineer, Chris Peterson, who explained that if you’re using Mozilla you’ll experience slowdown when attempting to use YouTube.
On July 24th, 2018 Peterson made a series of tweets about the issue and how to fix it.
YouTube serves a Shadow DOM polyfill to Firefox and Edge that is, unsurprisingly, slower than Chrome’s native implementation. On my laptop, initial page load takes 5 seconds with the polyfill vs 1 without. Subsequent page navigation perf is comparable.
— Chris Peterson (@cpeterso) July 24, 2018
To fix YouTube on Edge, you can install the Tampermonkey extension for Edge and this “YouTube Restore Classic” user script:https://t.co/Hf5Pn3Bnx3https://t.co/tccF4fVh9K
— Chris Peterson (@cpeterso) July 25, 2018
He noted that Mozilla takes five seconds to load compared to the one second to load on Chrome when using a 200Mbps setup.
According to CNET, a Google spokesperson told them that YouTube performance on Firefox was the same as it has been since the site redesign, according to their “latest metrics”. However, if YouTube has been loading slow since the site redesign then it doesn’t refute what Peterson mentioned in the series of tweets.
Google has been playing fast and loose with throttling, filtering, and censoring content at their own discretion. This has resulted in a number of changes in the way people find content on YouTube, in the way they find content on search engines, and the way that people gain access to information. Earlier this year the company attempted to remove hundreds of websites from Google News, and only fixed the problem after the issue spread across social media. The company then blamed it on a “bug”.
I attempted to reach out to Peterson to ask about the frequency of the slowdown when YouTube is updated and whether or not this has happened before, but he has me blocked on Twitter.