If you visit YouTube on the latest Chrome Canary you will notice that the site is broken with the page showing gray thumbnails for videos, the reason is as follows: Google has removed HTML imports in Canary and if you open developer tools and visiting the console tab, you get Error warning stating “HTML imports are deprecated and will be removed in M73, circa March 2019. Use ES modules instead”. Note that the single canary is affected, YouTube works fine on other Chrome channels such as beta, developer, and stable, as well as other browsers.
Web Components v0 Deprecation and Removal
At the end of the year, Google announced that it will discontinue and remove Web Components v0. Regarding this, Chrome 70 has started showing users deprecation for Custom Elements v0, Shadow DOM v0 and HTML Imports and after all, they should be removed in Chrome 73 which will be released on March 12, 2019 which is a week away from today.
You can read more about deprecating Web Components on the Polymer project website. The YouTube team is aware of this change and is well prepared in advance, so you don’t have to worry.
How he said by the Polymer Project team on twitter, if you are a developer who has built your sites with Polymer 1.x or Web Components, be sure to check them in Canary to ensure they are serving polyfills correctly. You can follow the discussion about it in this Google Groups forum thread.
Make Youtube work again in Chrome Canary
If you are an end user using cutting edge tech, you visit YouTube on stable Chrome or run Canary with the command line below, this is not recommended as it warns you that Chrome warns you that you are using a command line flag without support, security and stability will suffer. You can just ignore the warning and watch videos, but the info bar will pop up with every launch of Chrome browser.
March 5, 2019 Update: The Chromium team is aware of this and has managed to get a commit to revert this change in Canary, with the next update you have to wait for YouTube to work again.
March 6th. 2019 Update: The latest Canary update fixed the issue.
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