Style Engine Documentation

Last updated: 2026-03-01

Technical setup and operation guide for Style Engine.

Installation

Install Style Engine from the Chrome Web Store and pin it for quick access.

  1. Open the Chrome Web Store and search for Style Engine.
  2. Click Add to Chrome.
  3. Confirm the permission prompt.
  4. Pin the extension icon from the extensions menu.

Style Engine is built on Manifest V3 and works in Chromium-based browsers such as Chrome and Edge.

Quick Start

  1. Open any website.
  2. Click the Style Engine icon.
  3. Select a mode:
    • Global CSS
    • Global JS
    • Site CSS
    • Site JS
  4. Enable the rule (if required).
  5. Write your code in the editor.
  6. Press Ctrl + S or click Save.

Rules apply immediately. Reloading is usually not required.

/* example domain rule */
body {
  font-size: 16px !important;
  line-height: 1.6;
}

.sidebar-ads,
.promo-banner {
  display: none !important;
}

Core Concepts

  • Global CSS / Global JS: Applies to all websites while enabled.
  • Site CSS / Site JS: Applies only to the active domain.
  • Enable toggles: Control whether a rule runs.
  • Save: Persists changes.
  • Clear: Clears the editor (changes must be saved to apply).

How It Works

Style Engine injects the CSS and JavaScript you write into web pages.

  • Rules are stored locally in extension storage.
  • Domain matching determines where a rule set runs.
  • CSS is injected after page load.
  • JavaScript execution is scoped to the active page context.
  • Website source files are never modified.

For modern single-page applications (SPAs):

  • CSS automatically re-applies on route changes.
  • JavaScript re-run is optional (configurable in Settings).

Live Preview

Live JavaScript preview can be enabled in Settings.

  • Runs JavaScript while typing in the popup editor.
  • Useful for rapid UI testing and debugging.
  • Can be disabled at any time.

Backup & Restore

You can export and import your configuration using a local JSON file.

  • Backup includes global and per-site rules.
  • Restore imports rules safely.
  • No cloud sync is used.

Restore will overwrite existing rules.

Permissions

Style Engine requires host access to inject your saved rules on websites you enable.

It does not:

  • Collect browsing history
  • Transmit page content
  • Execute remote code
Typical permissions:
- activeTab
- storage
- scripting
- host permissions (only for sites you enable)

If you grant access to “All sites”, it is solely to allow your own rules to apply globally.

Troubleshooting

  • Rules not applying: verify domain match and ensure the rule is enabled.
  • No visible change: inspect selectors in DevTools and check specificity.
  • SPA sites not updating: confirm SPA support setting is enabled.
  • JS not executing: check for syntax errors in DevTools console.
  • Conflict with site styles: increase specificity or use !important selectively.
  • Strict CSP sites: some websites may restrict script execution.
  • After browser update: disable/enable the extension once and retest.
/* quick specificity test */
html body .target-class {
  color: #111 !important;
}

Privacy

Style Engine operates as a local customization tool.

  • No tracking
  • No analytics
  • No external data transmission

All rule sets are stored locally in your browser.
The extension injects only the code you explicitly write and save.

Publisher: Glitchid
Website: https://glitchid.com
Support: [email protected]

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