openstyles/stylus
Stylus
Stylus is a browser extension for installing, managing, and editing user-created CSS themes that customize the appearance of websites. It provides a central interface for organizing, enabling, disabling, and removing installed styles, and includes a built-in CSS editor with syntax highlighting and linting support.
The extension supports the UserCSS format, allowing users to install themes from .user.css files or URLs, and generates a basic UserCSS template with required metadata fields when creating new styles. Stylus can watch local .user.css files for changes and automatically apply edits to matching web pages without manual refresh, and it checks for and applies updates to installed styles using configurable per-style and global update settings.
Stylus enables users to customize style properties at install time through a dynamic dialog generated from @var definitions, and provides backup and restoration of style collections as JSON files compatible with other userstyle managers. The extension also supports cross-device synchronization of installed styles through cloud storage services like Dropbox, Google Drive, or WebDAV.
Features
- Userstyle Personalization - A browser extension for installing, managing, and editing user-created CSS themes that restyle websites.
- Userstyle Managers - Organizes, enables, disables, and removes installed CSS themes through a central management interface.
- Browser - Installs and applies user-created CSS themes from supported repositories to restyle any website.
- UserCSS - Detects .user.css files and presents an install button to add UserCSS themes to the extension.
- CSS Theme Authoring - Provides a built-in CSS editor with syntax highlighting and linting for authoring complete website themes.
- Style Injections - Injects user-authored CSS into web pages by intercepting and modifying the browser's style resolution pipeline.
- CSS Theme Editors - Provides a built-in CSS editor with syntax highlighting, linting support, and live reload for external editors.
- Style Editors - Allows creating and editing custom CSS rules for specific sites using a built-in editor with syntax highlighting.
- Userstyle Auto-Updaters - Checks for and applies updates to installed CSS themes using configurable per-style and global update settings.
- UserCSS - Extracts and validates structured metadata from CSS comments to enable variable configuration and update checks.
- CSS File Watchers - Monitors CSS file changes and reapplies styles instantly without restarting the app, enabling live editing.
- CSS Live Reload Watchers - Watches local .user.css files and applies edits to matching pages without manual refresh.
- Userstyle Version Updaters - Checks the installation source or @updateURL for a newer version and reinstalls the style when an update is available.
- Live Reloading - Watches a local .user.css file for changes and automatically applies edits to matching web pages.
- UserCSS Variable Dialogs - Generates a dynamic form from @var definitions to let users customize style properties at install time.
- UserCSS Variable Configurations - Displays a dialog with input controls for each @var definition to customize colors, fonts, and other style properties.
