YouTube displays ad blocker warning message to users. The message says that in addition to subscribing for an ad-free video experience, using an ad blocker can also reduce video quality, which is H. resolution.

YouTube has recently taken steps to remove ad blockers to help creators. The system was initially introduced in some countries but is now gradually being rolled out to others. As part of this measure, users will not be able to view videos on YouTube if they have an ad blocker installed.

Users are advised to subscribe to YouTube to watch ad-free videos. Users will now see a pop-up message if they have an ad blocker installed. These messages suggest that instead of using an ad blocker, subscribe to YouTube Premium.

Additionally, it warns that using ad blockers will reduce the resolution quality of YouTube videos. Google Chrome, Edge or Firefox all browsers have ad blockers and YouTube says the video quality is degraded.

YouTube can also be played in the background on your smartphone or computer with a YouTube Premium subscription for ad-free viewing. The YouTube Music app lets you watch and listen to tons of content. 

Meanwhile, the European Union has complained that YouTube does not allow viewing of videos without ad blockers.