This is no longer true, youtube has already migrated to Polymer v3 which is based on the v1 web components standards so it no longer has any problems with the latest versions of all browsers (except edge but that's already not a problem as long as you use the chromium-based build)
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This is no longer true, youtube has already migrated to Polymer v3 which is based on the v1 web components standards so it no longer has any problems with the latest versions of all browsers (except edge but that's already not a problem as long as you use the chromium-based build)