Global or per-site
Keep universal rules separate from isolated domain-specific CSS and JavaScript, with independent CSS and JavaScript controls.
Browser extension / Free
Style Engine
Your browser. Your rules.
Apply your own CSS and JavaScript globally or per domain, with local-only storage, automatic saving and precise control.
- Version
- 1.3.0
- Status
- Available
- Type
- Free
- Browsers
- Chrome · Edge · Firefox
- Initial release
- March 1, 2026
- Updated
- September 2026
01 / 05
Core / Capability
Made to stay out of the way.
SPA-aware
CSS stays applied across modern route changes, with optional JavaScript rerun behavior for SPA navigation.
Local-only
Rules and settings remain in local browser storage. No tracking, analytics, remote code or browser sync storage.
Backup and restore
Export the complete configuration as a local JSON file and restore it safely.
Get Style Engine
Available now.
Available for Chrome, Edge and Firefox.