User JavaScript and CSS icon

User JavaScript and CSS

by tenRabbits · Developer Tools
Manifest V3 Free
View in Chrome Web Store Data as of 15 Oct 2026

User JavaScript and CSS on any website

Users
200K
0 in 30 days
Rating
4.5 / 5
−0.26 in 30 days
Ratings
662
+1 in 30 days
Store rank
#1,196
#1,077 among extensions
Version
3.1.2
updated 7 Jul 2025

Users

monthly, 3 years
30K115K200KAug 2023Apr 2025Oct 2026
Latest, 15 Oct 2026: 200,000 usersMove the mouse over the chart for any month

Ratings count

monthly, 3 years
100381662Aug 2023Apr 2025Oct 2026
Latest, 15 Oct 2026: 662 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About User JavaScript and CSS

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.

Growth

WindowUsersChangeRatingsRating
7 days0+0.0%+1−0.26
30 days0+0.0%+1−0.26
6 months0+0.0%+12−0.27
1 year0+0.0%+34−0.28

Chrome Web Store search rankings

Where User JavaScript and CSS appears when people search the store, with the 30 day change
Search phrasePosition30 days
javascript#2+1
jquery#40
inject#90
css editor#130
rule#24+14
bug fixes#28+24
version#30+8
script#39+3
options#42+21

Version history

10 versions recorded
3.1.27 Jul 2025
3.0.61 Jul 2024
3.0.513 Jun 2024
3.0.37 Jun 2024
3.0.24 Jun 2024
3.0.13 Jun 2024
3.0.02 Jun 2024
2.1.11 Feb 2024

Details

Category
Developer Tools
First seen
8 May 2020
Size
1.7 MB
Languages
en, ru
Pricing
Free
Extension ID
nbhcbdghjpllgmfilhnhkllmkecfmpld

Permissions and risk

Moderate riskimpact 3, likelihood 1
Permissions
storagetabsunlimitedStorageuserScriptsscripting
Site access
http://*/https://*/

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