Stylus is a browser extension to restyle the websites via CSS themes, compatible with Chrome, Firefox, and any Chromium-based browsers.

## Highlights

* No analytics/tracking - this is our foundational principle as Stylus was created solely because the original Stylish extension was sold to a Web analytics company.
* Lots of themes in external galleries like [USW](https://userstyles.world/explore), [USO archive](https://uso.kkx.one/browse/categories), [greasyfork](https://greasyfork.org/en/scripts/by-site/*?language=css):
  * click the `Find` button in the popup UI,
  * click the screenshot to apply the style to the website,
  * click the screenshot again to uninstall the style.
* [UserCSS](https://github.com/openstyles/stylus/wiki/Usercss) styles with advanced customization installable from any raw plain text URL.
* Cloud sync for Dropbox, GDrive, OneDrive, or any WebDAV-compatible server.
* Backup to a JSON file compatible with other userstyles managers.
* Auto-update for styles, configurable in each style and globally in the options.
* Lightweight content script (~10kB) in the web pages runs in about a millisecond.
* Lots of options to configure UI and behavior.
* Built-in editor for your own CSS themes (CSS/LESS/Stylus) that highlights problems using up-to-date linters ([Stylelint](https://stylelint.io/) and [CSSLint-mod](https://github.com/openstyles/csslint-mod)) with customizable rules.
* Support for external IDE or advanced editor via the [live reload feature](https://github.com/openstyles/stylus/wiki/Writing-UserCSS#live-reload-on-the-fly-previewingwhen-developing-styles-locally-in-another-editoride) e.g. you can write SASS/SCSS by setting up a build step to produce standard CSS in a separate file that will be tracked by Stylus.

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## Screenshots

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* Manager

   ![Style manager](.github/screenshots/manager.png)

* Installer

  ![Installer](.github/screenshots/installer.png)

* Editor

  ![Style editor](.github/screenshots/editor.png)

* Popup search

  ![Popup inline search](.github/screenshots/popup-search.png)

* Popup config

  ![Popup config for usercss](.github/screenshots/popup-config.png)

* Manager config

  ![Style manager config for usercss](.github/screenshots/manager-config.png)

* Options

  ![Options](.github/screenshots/options.png)

</details>

## Releases

1. [Chrome Web Store](https://chromewebstore.google.com/detail/stylus/clngdbkpkpeebahjckkjfobafhncgmne) or [beta](https://chromewebstore.google.com/detail/stylus-beta/apmmpaebfobifelkijhaljbmpcgbjbdo)<br>for modern Chrome (v128+) and Chromium-based browsers like Brave, Opera, Vivaldi.

2. [Mozilla addons](https://addons.mozilla.org/firefox/addon/styl-us/) or [beta](https://github.com/openstyles/stylus/releases) (as an xpi file)<br>for Firefox and any Gecko-based browser.

3. [Zip file](https://github.com/openstyles/stylus/releases) with `-mv2` suffix to _load as an unpacked extension_<br>for older Chromium-based browsers which only support ManifestV2 version.

## Pre-release test builds (nightlies) [![badge](https://github.com/openstyles/stylus/actions/workflows/ci.yml/badge.svg)](https://github.com/openstyles/stylus/actions/workflows/ci.yml)

1. click a workflow entry in https://github.com/openstyles/stylus/actions/workflows/ci.yml,
2. download the file in `Artifacts` - this requires a github.com account,
3. install it, see [the instruction](https://github.com/openstyles/stylus/wiki/Install-Stylus-from-GitHub).

## Asking questions, participating, contributing

* Bugs, discussions, questions, ideas, pull requests: https://github.com/openstyles/stylus
* Wiki for many common tasks and questions: https://github.com/openstyles/stylus/wiki
* Discord: https://discordapp.com/widget?id=379521691774353408 ![Discord](https://img.shields.io/discord/379521691774353408.svg)
* Helping with translation: https://explore.transifex.com/github-7/Stylus/
* Guidelines and more info: https://github.com/openstyles/stylus/CONTRIBUTING.md

## License: [GPLv3](./LICENSE)

* Copyright &copy; 2017-2025 [Stylus Team](https://github.com/openstyles/stylus/graphs/contributors)
* Copyright &copy; 2005-2014 [Jason Barnabe](jason.barnabe@gmail.com) for the ever diminishing parts of the original [Stylish](https://github.com/stylish-userstyles/stylish/).
* Licenses of modified external libraries: [vendor-overwrites](./src/vendor-overwrites).