No need for extensions or any third-party software to make Youtube always play video in Theater mode. Go to https://www.youtube.com Open dev tools of the browser you are using (Press F12 or Right-click -> Inspect) Select Console tab Paste below code and Enter: document.cookie = ‘wide=1; expires=’+new Date(‘3099′).toUTCString()+’; path=/’;
It is so easy to do that. If you don’t want to see annotations (or cards) for any video whatsoever, you can disable all interactive elements by heading to settings, clicking on Playback from the Account Settings panel on the left, and then unchecking the box for “Show in-video info cards”
The easiest way to do that is using AdBlock. 1. Open your web browser and go to the Adblock Settings as shown. 2. Click on the Customize option in the left pane. 3. Here in the Customize AdBlock section, locate and click the Edit button next to Manually edit your filters. 4. Then, add the following links and click on the Save button. youtube.com###chat