Dark mode for the sites you choose

Shadeflip is a free, small extension for Firefox and Chromium browsers. Click the extension button to switch the site you're on between light and dark.

It saves the setting for that site, so that site looks the same the next time you visit. Other sites keep their usual colors.

Get it

Use the Chrome Web Store for Chrome, Edge, Brave and other Chromium browsers, and Firefox Add-ons for Firefox.

How it works

The Shadeflip button is in your browser toolbar. Instead of clicking it, you can also press Alt/Opt+Shift+D.
Before it changes anything, the extension checks the page. If you asked for dark and the site is already dark, it leaves the page as it is.
If you want dark on most sites, set dark as the default in settings. Then switch back the few sites that look better light.

How it darkens a page

Shadeflip inverts the page's colors and then inverts photos and video a second time, which puts them back to their real colors. This is fast and works on almost any site. The trade-off is that some colors, such as a brand's blue or orange, can come out slightly different.

The same example.com article twice: in its normal light colors, and after Shadeflip turns it dark. The photo keeps its real colors in both. — The same article before and after Shadeflip.

Privacy

You dot no need any account to sign up or login for, and the extension doesn't collect analytics or make network requests. Your settings stay in your browser.

The extension is under 20 KB of open source JavaScript and CSS. It uses no libraries and doesn't load code from anywhere else.
It saves only the sites you've set, and nothing in a private window.
It doesn't leave a fixed marker on the page, so a website can't use it to recognize you or follow you between sites.

For the details, see how it works and why it's safe and the privacy policy.