Google’s new design for YouTube reportedly loads up to five times slower on Edge and Firefox than on Chrome. Being that a deprecated API is involved, many believe the company is intentionally stifling its competitors. Firefox and Edge users may revert to the original design by installing certain extensions. In a thread on Twitter, Mozilla's Technical Program Manager has stated that YouTube's Polymer redesign relies heavily on the deprecated Shadow DOM v0 API, which is only available in Chrome. This in turn makes the site around five times slower on competing browsers such as Microsoft Edge and Mozila Firefox.