Why it's a strong pick

Turn Off the Lights has been built by one developer, Stefan vd (Stefan Van Damme), since December 2009. It does two jobs: it dims the page around a video, and its Night Mode turns white backgrounds black. The vendor describes it as free and open source, with a donation appeal. The trade-off: it asks for access to all sites, which the store listing explains one permission at a time.

What it does

The original feature is the "lights off" effect. Click the lamp button and the page darkens around a video player so the video stands out. You can set how strong the dimming is with opacity shortcuts.

Night Mode is a separate feature. The vendor says it turns white page backgrounds dark, and you can set times when it switches on.

Key features

Lights off for video. Dims everything around the player. Shortcut: Ctrl+Shift+L.
Adjustable opacity. Change how dark the page gets, with shortcuts.
Night Mode. White backgrounds turn black, with customizable activation times.
Whitelist and blacklist. Choose sites where Night Mode runs or stays off.
Video filters. Grayscale, sepia, invert, contrast and saturation.
YouTube extras. Auto HD and Auto Wide.
Mouse-wheel volume on HTML5 video, and audio visualization.

Who it's for

Turn Off the Lights suits people who watch a lot of video in the browser and want the dimming effect and a Night Mode in one tool. It also fits people who prefer open-source code and a long-running project. If you want a dark theme that works on all pages with fine controls, compare Dark Reader and Night Eye. See Dark Reader alternatives for more.

Is Turn Off the Lights open source?

Yes. Its GitHub README gives the license as GPLv2, so you can read the code. The vendor's site calls the extension free and open source and asks for donations. That means no paid tier is described, and the project relies on gifts. We could not confirm anything about accounts, and no sign-in step is described.

What permissions does Turn Off the Lights ask for?

The store listing explains each one. contextMenus adds a "Darken this page" menu item. tabs is used for the welcome page, detecting a playing video, screenshots and dimming all tabs. storage holds settings and syncs them with your browser account. scripting injects JavaScript and CSS.

webNavigation loads Night Mode before a page finishes loading. Access to all URLs puts the lamp button on every site.

What does Turn Off the Lights do with my data?

The store listing says the developer will not collect or use your data. It also says the extension does not collect or store personal data and that video enhancements are processed locally, with no ads or crypto mining. Those are the listing's own statements. Read the developer's privacy policy before you install if you want more detail.

Does Turn Off the Lights work with Manifest V3?

We could not confirm the store build. The developer's blog describes a Manifest V3 beta and says some features were dropped, such as Camera Motion and Speech Recognition. If a feature you want is missing, that post explains why. Check the listing for the current state.

FAQ

Which browsers does it support? Its README lists Chrome, Firefox, Opera, Safari, Brave, Edge and others.

Is it free? The vendor calls it free and open source and asks for donations.

Does Night Mode work everywhere? The vendor's coverage claim is its own and we did not verify it. Test it on the sites you use, because some may not turn dark.

Good to know

The lamp button and Night Mode run on all sites, so the extension has broad access. Night Mode flips white backgrounds to black, so images and unusual site designs can look off. Use the whitelist and blacklist to keep it off where it causes trouble.

Other dark mode & reader tools to compare

Turn Off the Lights is one of 10 picks in our Dark Mode & Reader Tools guide, which compares them side by side and explains how to choose. The other picks:

Dark Reader: An open-source dark mode for websites. Free extension, with brightness, contrast and sepia controls.
Night Eye: A dark mode extension that adjusts each page's elements instead of flipping every color. Free Lite plan with limits, paid plans above it.
Midnight Lizard: An open-source colour-scheme tool for websites. Dark, light and grayscale modes plus a blue-light filter.
Reader View: A reader extension built on Mozilla Readability. Opens an article in a clean page, with fullscreen reading and text-to-speech.
Reader Mode: A distraction-free reader with accessibility tools, highlighting and text-to-speech. Free plan with limits, paid Premium.
Chrome Reader Mode: A reader mode that can also save articles offline, highlight and take notes. The listing is now titled Quiet Reader.
Just Read: A reader mode for article pages, made by one developer. Free core, paid subscription for extras.
Clearly Reader: A reader mode with an AI assistant. A free plan, plus paid Pro and Subscription plans.
Stylus: Restyle websites with CSS themes, such as dark themes, that you install or write yourself. Not a one-click dark mode. Open source.