Join us to show up for other Firefox users 🦊. Earn fun badges and Mozilla swag vouchers! Find out more: https://mzl.la/askafox150

Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Sykje yn Support

Mij stipescams. Wy sille jo nea freegje in telefoannûmer te beljen, der in sms nei ta te stjoeren of persoanlike gegevens te dielen. Meld fertochte aktiviteit mei de opsje ‘Misbrûk melde’.

Mear ynfo

Dizze konversaasje is argivearre. Stel in nije fraach as jo help nedich hawwe.

Tab/Program Brightness

  • 2 antwurd
  • 1 hat dit probleem
  • 155 werjeftes
  • Lêste antwurd fan cor-el
  • Argivearre

Hello support,

is there any way (other than the one plugin I found that did not work for some reason) to adjust firefox' general brightness (or that of an individual tab) ?

Also changing my monitors brightness would not work for me as I am trying to test a website I develop (using firefox to visualize it) and it is rather just the large difference between my editor (which's brightness you can not adjust) and the browser that is very unpleasent when I switch back and forth (like when trying to fix a bug).

Kindest regards.

Jonas Behr

Hello support, is there any way (other than the one plugin I found that did not work for some reason) to adjust firefox' general brightness (or that of an individual tab) ? Also changing my monitors brightness would not work for me as I am trying to test a website I develop (using firefox to visualize it) and it is rather just the large difference between my editor (which's brightness you can not adjust) and the browser that is very unpleasent when I switch back and forth (like when trying to fix a bug). Kindest regards. Jonas Behr

Alle antwurden (2)

I found this one that can dim the current page, but because it has limited permissions, you have to click the button on every page load (except going Back, the page remains filtered going Back):

https://addons.mozilla.org/firefox/addon/brightnessslider/

If you look under the hood (https://github.com/dkameoka/brightness-addon/blob/main/brightness.js#L10), it injects CSS to apply a brightness filter. For example, 80% brightness:

html {filter: brightness(80%) !important;}

Which is something you could apply automatically to your site using the Stylus extension (https://addons.mozilla.org/firefox/addon/styl-us/) or, with a little more difficulty, a userContent.css file.

A simple bookmarklet:

javascript:void(document.querySelector('html').style.filter='brightness(80%)')