Greasemonkey - YouTube - Video Dimmer

Usage and description

Install the Greasemonkey script below to add a dimmer button to YouTube videos.

Versions

• 2026-09-26
  • First release.

Installation instructions

Firefox

• Install Greasemonkey (https://addons.mozilla.org/en-Us/firefox/addon/greasemonkey/)

Chrome

• Install Tampermonkey (https://chrome.google.com/webstore/detail/tampermonkey/dhdgffkkebhmkfjojejmpbldmpobfkfo?hl=en)
• NOTE: You must enable Developer Mode to make this extension work now.

Opera

• Install Violent Monkey (https://addons.opera.com/en/extensions/details/966c30b450467e201973e7ee3ed48a8bc5253ae6/)

Safari

• Install Tampermonkey (https://tampermonkey.net/index.php?ext=dhdg&browser=safari)
• Once installed, you must restart Safari.

Safari (iOS)

• Install Userscripts (https://apps.apple.com/us/app/userscripts/id1463298887)
• Click the link below
• Click the puzzle piece icon (extensions) in the upper left next to the URL
• Click "Userscripts"
• Click "Tap to install"
• Scroll down if needed and install

The Script

Once you have installed Greasemonkey, click this link to install the script.