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Firefox Dark Mode Features
Everything You Need for the Best Firefox Dark Mode
Turn Off the Lights is not just a simple firefox dark mode. It is a complete browser enhancement built to give you full control over how every website looks in the dark.
Firefox Add-on, Official Store
Available directly from addons.mozilla.org — install with one click, no developer mode needed.
Dark Every Website in Firefox
Night Mode applies to all sites you browse in Firefox — YouTube, Reddit, news, Wikipedia, social media, and more.
Element-Level Color Control
Choose to darken only backgrounds, only text, only links, or any combination — more precise than any simple CSS invert.
Sunrise/Sunset Scheduling
Automatically switch Firefox to dark mode at sunset and back to light at sunrise, synced to your local time.
YouTube Cinema Mode in Firefox
Dim YouTube's background for a cinema-like experience — a feature originally built for Firefox users.
Open-Source & Auditable
Full source code on GitHub under GPLv2. No secrets, no trackers, no ads.
How It Works
Enable Firefox Dark Mode in Under 30 Seconds
Turn Off the Lights is available in every major browser store and takes less than 30 seconds to install and activate. No configuration needed — it works instantly.
Visit Firefox Add-ons
Go to addons.mozilla.org and search for 'Turn Off the Lights', or click the install button above.
Click Add to Firefox
Firefox will ask for permission confirmation. Approve and the extension installs in seconds.
Open Options → Night Mode
Right-click the lamp icon in the Firefox toolbar, select Options, and go to the Night Mode tab.
Enable & Customize
Toggle Night Mode on. Every website in Firefox turns dark. Customize colors, scheduling, and element-level control.
Browser Support
One Firefox Dark Mode Extension. Every Browser.
Turn Off the Lights is available across all major desktop browsers. Install it in one browser and your Night Mode settings sync automatically to others.
⬇ Install Free — Firefox Dark Mode
FAQ
Frequently Asked Questions About Firefox Dark Mode
Install Turn Off the Lights from the Mozilla Firefox Add-ons page, go to Options → Night Mode, and enable the switch. All websites in Firefox will load in dark mode.
Firefox has a dark theme for its UI. For websites, you need an add-on. Turn Off the Lights applies Night Mode to every website you visit in Firefox.
Yes — it is available on the official Mozilla Firefox Add-ons page at addons.mozilla.org. It is fully reviewed, free, and open-source.
Yes. Turn Off the Lights adds a Night Mode switch directly on every YouTube page in Firefox, plus cinema dimming, Auto HD, Atmosphere Lighting, and more.
Why Turn Off the Lights
The Most Complete Firefox Dark Mode Solution Available
Firefox users searching for Firefox dark mode often discover that Firefox's own dark theme only covers the browser interface — not the websites themselves. Turn Off the Lights is the solution.
Night Mode for All Websites in Firefox
Firefox's built-in dark theme covers menus, toolbars, and the address bar. Turn Off the Lights extends dark mode to every webpage you visit in Firefox — converting bright white backgrounds to your chosen dark color across all sites instantly.
Installed in One Click from Firefox Add-ons
Turn Off the Lights is available directly from the official Mozilla Firefox Add-ons page. No third-party stores, no sideloading required. Install it in under 10 seconds and Firefox dark mode is active across all websites immediately.
Advanced Night Mode Customization in Firefox
The Night Mode in Turn Off the Lights goes far beyond a simple CSS invert filter. Choose exactly which elements to darken — background, text, links, buttons, or borders — independently. The Standard Theme uses a CSS filter for 100% website compatibility, while advanced modes let you fine-tune every color.
Open Source, Private, and Free — Always
Turn Off the Lights collects no personal data, displays no advertising, and charges nothing. The extension is fully open-source under the GNU General Public License Version 2 (GPLv2), with its complete source code available on GitHub for anyone to inspect. It has been in continuous development since 2009 and remains one of the most trusted browser extensions available, with millions of active users across all major browsers. Stefan Van Damme is the solo developer and has maintained the extension with monthly updates for over 15 years.