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Preview of JS and CSS snippets for web

JS and CSS snippets for web by Yupma

Run peristent JavaScript and CSS code snippets on any website.

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About this extension
Snippet Injector lets you add your own code to websites based on URL rules. Create and manage snippets that run automatically when pages load. Perfect for developers, QA engineers, power users, and anyone who wants to customize websites or test scripts.

Key Features
- Inject JavaScript or CSS: Run code in the page’s main world or isolated CSS safely.
- Flexible URL rules: Apply snippets to all websites, a single domain, exact URLs, or custom regular expressions.
- Enable or disable snippets: Turn snippets on or off without deleting them.
- Persistent across reloads: Snippets automatically run when pages reload.
- Dynamic page support: Works with modern single-page apps (SPAs) and iframe-based sites.
- Built-in code editor: Write and edit snippets directly in the popup using a clean editor interface.

Who It’s For
- Web developers testing or debugging code.
- QA engineers automating workflows.
- Power users customizing web apps or dashboards.
- Anyone looking for a lightweight alternative to Tampermonkey.

Permissions & Privacy
- Tabs: Check the active tab URL to run matching snippets.
- Storage: Save your snippets and settings locally.
- Scripting: Inject JavaScript and CSS into websites safely.
- No data is collected, all code runs locally, and your snippets stay private.
- Take control of your browser. Customize websites your way with Snippet Injector.
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Permissions and data

Required permissions:

  • Access browser tabs
  • 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
1.0.0
Size
1.03 MB
Last updated
5 days ago (Jan 13, 2026)
Related Categories
  • Web Development
  • Privacy & Security
  • Search Tools
License
All Rights Reserved
Version History
  • See all versions
Tags
  • facebook
  • google
  • privacy
  • reddit
  • user scripts
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