Style Engine – Custom CSS & JavaScript by Glitchid

Style Engine lets you apply your own CSS and JavaScript rules to websites. Built for developers, designers, and power users who want precise UI control without touching server-side code.

Apply custom CSS and JavaScript to websites globally or per domain. Lightweight, local-only, and fully user-controlled.

Key features

Global rules: Apply CSS/JS to all websites (typography tweaks, accessibility improvements, debugging overlays).
Per-website rules: Domain-isolated rule sets with independent enable/disable controls.
SPA navigation support: CSS automatically re-applies on route changes; JavaScript re-run can be enabled in Settings.
Optional live preview: Live JavaScript preview while typing in the popup editor (can be disabled in Settings).
Backup & Restore: Export/import your full configuration safely with a local JSON backup.
Flexible feedback: Desktop notifications, inline feedback, or silent mode.
Multi-language interface: English, Spanish, German, French, Italian, Dutch, Polish, Portuguese, Turkish, and Russian.

Common use cases

Create custom dark mode rules for sites that don’t support it.
Hide intrusive UI elements (banners, promos, sticky bars) with a few selectors.
Automate repetitive tasks with small JavaScript snippets.
Normalize fonts, spacing, and layout for a consistent browsing experience.

Privacy & safety

No tracking: Style Engine does not collect browsing data or analytics.
Local-only: Your rules are stored locally in your browser.
User-controlled: The extension runs only the code you explicitly write and save.
No remote code: No external scripts are downloaded or executed.

Links

Website: https://glitchid.com/products/style-engine/
Documentation: https://glitchid.com/products/style-engine/documentation/
Privacy: https://glitchid.com/privacy/style-engine-privacy/
Terms: https://glitchid.com/terms/style-engine-terms/
Support: support@glitchid.com

Publisher: Glitchid