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User JavaScript and CSS icon

User JavaScript and CSS

by tenRabbits

Developer tools javascript css userscripts userstyles web-development customization developer-tools code-injection
User JavaScript and CSS icon

User JavaScript and CSS

by tenRabbits

Developer tools javascript css userscripts userstyles web-development customization developer-tools code-injection
Screenshot 1
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Quick Look

Enhance any website by injecting custom JavaScript and CSS rules with this versatile extension.

AI Overview

Who is this for?

Web developers and users who want to customize website appearance and functionality.

Key Features

  • → Inject custom JavaScript and CSS
  • → URL masking for rule application
  • → Instant execution of rules
  • → Support for custom library includes
  • → MV3 compatibility

Reviews Analysis

Overall Sentiment

Mostly Positive

Users find the extension highly effective for customizing websites with JavaScript and CSS, appreciating its features and frequent updates, though some encounter minor bugs.

Note: AI analysis focuses on the substance and recency of reviews, which may differ from the overall store rating.


What Users Love

  • ✓ Excellent for injecting custom JS/CSS
  • ✓ Regular and significant updates
  • ✓ Useful URL masking feature

Points to Consider

  • × Occasional bugs reported
  • × Some users found the interface complex initially

Official Description

From the Developer


User JavaScript and CSS on any website

Userscript's and userstyle's — simple extension to inject own JavaScript or CSS rules to any page.

Features:

  • Instant execution
  • Custom libs include
  • URL masking allows use one script or CSS on many pages

Documentation: https://tenrabbits.github.io/user-js-css-docs/

Change log: Version 3.1.0

  • Starting from Chrome version 138, the method for allowing user scripts in the browser has changed
  • Fixed a bug where styles weren't removed when a rule was deleted
  • Fixed a bug where not all rules applied to the page were shown in the rules popup

Version 3.0.6 beta

  • try catch wrapper removed
  • CSS injection improved
  • added button to save converted URL

Version 3.0.5 beta

  • the mode of injection of styles into the DOM has been returned
  • minor fixes

Version 3.0.3 beta

  • modules are now in the same scope
  • CSS injection improvement
  • and other minor fixes

Version 3.0.2 beta

  • hotfix: fixed bug with registration and deletion of scripts
  • added feature to change start scripts before page loading
  • added feature to strictly read URL patterns

Version 3.0.1 beta

  • Improved CSS injection
  • Fix loading external modules when replacing storage

Version 3.0.0 beta

  • The extension has been moved to MV3
  • Added option to inject scripts and styles in iframe
  • Added the feature of live CSS
  • Added the One Dark theme and a few other improvements

Version 2.0.0

  • 90% of the code has been rewritten;
  • Improved UI;
  • Added SASS support;
  • Added Prettier formatter
  • Other minor improvements

Version 2.0.0

  • 90% of the code has been rewritten;
  • Improved UI;
  • Added SASS support;
  • Added Prettier formatter
  • Other minor improvements

Version 1.2.8

  • Added function for naming rules
  • Updated translations

Version 1.2.7

  • Updated all extension libraries to current versions

Version 1.2.6

  • Fixed error in console "Unchecked runtime.lastError: The message port closed before a response was received"
  • Improved domain getter from URL
  • Updated Ace Editor and jQuery to latest

Version 1.2.5

  • Resolved bug with '@import' and "Auto-important css" feature
  • "Auto-important css" feature now disabled by default
  • Added feature to exclude URL's by '!' symbol at start
  • Updated jQuery and Ace editor to last versions
  • Other small fixes

Version 1.2.4

  • Added manual cloud sync in testing mode
  • Improved "auto-important css" feature
  • Other small fixes

Version 1.2.1

  • Fixed algorithm of "high priority CSS"

Version 1.2.0

  • Added toggle button in site list
  • Added documentation tab
  • Added 'Vintage mode' option to Ace Editor
  • Updated jQuery, Ace Editor to last versions
  • Other small fixies

Version 1.1.5

  • Returned old method injection and added option to toggle this. Alternative method has feature to avoid CORS issues, but has only DOM access to site (no JS context). Old and now primary method is injecting by <script> tag on site bottom.
  • Added scroll past end in editor

Version 1.1.2

  • Minor bug fixes

Version 1.1.0

  • Added new injection system that increased perfomance
  • Added feature: few URLs in one rule (separate by commas)
  • Added word wrap setting
  • Added CSS auto !important option
  • Minor changes

Version 1.0.2

  • Hot fixes

Version 1.0.0

  • Full redesign of extension
  • Added more settings
  • Added toggleable counter on extension icon

Version 0.98

  • Fix bug that prevent create new rules
  • Minor changes

Version 0.96

  • Full redesign of extension interface
  • 80% code of extension core has been rewritten
  • New feature: change URL field and mask with "*" symbol (eg *.expample.com)
  • Editor window opens in new tab in split layout
  • Disabled autosave feature
  • Configurable editor in settings
  • New icon

Version 0.94

  • Hotfix editor opening bug

Version 0.93

  • Fixed a bug where JavaScript is not always inserted in a page
  • Outdated processes are disabled

Version 0.92

  • Code autosave work on all pages

Version 0.91

  • Fix ".co.uk" zone parse
  • Other small fixes

Version 0.90

  • Improve core
  • Add feature to load own libraries

Beta test. If you find any problem or have a question contact me on email.

Your extension? Let us know if we can update or correct anything!

Key Info

  • Rating:
    4.8/5.0

    (632 ratings)

  • Users:200,000
  • Version:3.1.2
  • Updated:Jul 07, 2025
  • Developer:Visit Website →

Stats from Chrome Web Store


Add to Chrome / Chromium

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