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Preview of UserScript Pro: Custom JS & CSS

UserScript Pro: Custom JS & CSS by aitchess

A premium, minimalist developer tool to inject custom JavaScript and CSS into any website. Features a boutique workspace with Ace Editor, real-time injection, and advanced URL matching.

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Extension Metadata

About this extension
UserScript Pro is a high-end, boutique developer extension designed for precise web customization. It provides a clean, monochromatic environment for managing and injecting custom scripts and styles into web pages.

Key Features: - Advanced Code Editor: Powered by Ace Editor with syntax highlighting for JS and CSS. - Real-time Injection: Instantly run your code on the active tab without refreshing. - Smart Pattern Matching: Support for Glob patterns and Regex to target specific URLs. - Pro Workspace: Ultra-minimalist, distraction-free UI inspired by premium developer tools. - Secure & Performance-focused: Built with Manifest V3 and safe DOM APIs.
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Version
1.1
Size
184.59 KB
Last updated
9 days ago (Jan 28, 2026)
Related Categories
  • Web Development
  • Appearance
License
MIT License
Version History
  • See all versions
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