A recent issue has been brought to the attention of some YouTube users who have noticed a five-second delay when playing videos on the Firefox browser. The reason behind this delay is believed to be related to ad-blocking extensions in the Firefox browser, as users claim that it is not a Firefox bug but rather a code that Google has entered into YouTube. This code has been identified as 5E3 in the polymer script link.
YouTube confirmed early November that it was implementing global measures to combat ad blockers in browsers. The platform increased warnings urging users to avoid using ad blockers or subscribe to YouTube Premium, and if users continue with ad blockers, video playback may be blocked. As a result, there has been an increase in uninstalls of ad blockers and installations of alternative programs such as AdGuard, AdLock, and Ghostery.