About Stylus
Stylus is a userstyles manager: instead of one automatic dark mode, it lets you apply custom CSS themes to any website. Dark themes are the most popular use, but you can also change fonts or hide clutter. It exists because of a scandal. The original Stylish extension was sold, and in 2018 a researcher showed it was sending users' browsing history to an analytics firm. Stylus began as an open source fork, and its README says it has no analytics or tracking.
A Find button searches theme galleries such as userstyles.world, and one click applies a style to the current site. You can also write your own in the built-in editor, which highlights problems as you type, and sync your styles through Dropbox, Google Drive, OneDrive or WebDAV. Chrome's build is Manifest V3 and Firefox marks the add-on Recommended.
The trade-off is effort. Stylus gives you the tools, not a finished dark mode, and the themes you install are written by other people, so stick to popular, well-reviewed ones. It has no Safari version. If you want to tinker, or want dark themes hand-built for specific sites, Stylus is the right choice, and it pairs well with Dark Reader.
Pros and cons
- Free, GPL-3.0 and built with no analytics or tracking
- Install ready-made themes from galleries, or write your own
- Built-in editor with linting, plus cloud sync and backups
- Active: version 2.4.17 shipped in October 2026
- Needs some CSS knowledge to get the most from it
- Third-party themes are code written by strangers
- No Safari version
Permissions
It can read and change data on all websites so it can inject styles, and it uses web request and navigation access to apply them as pages load. It also stores your styles locally and in any sync service you choose.
