CustomCSS Injector

- Apply any CSS rules for any websites, including iframes. - Whitelist and Blacklist functionality - Apply CSS rules to specific URLs, Domains or Globally - Syntax highlighting & line numbers - Update without page refresh

CustomCSS Injector: Control the Look of Your Web Pages

CustomCSS Injector is a unique Firefox add-on, powerfully designed to let you customize the appearance of any website as per your preference. It provides you with the power to change colors, backgrounds, resize elements and even hide those you find intrusive, all by applying your own CSS rules. The add-on includes features such as applying CSS rules based on specific URLs, Domains or Globally, coupled with a whitelist/blacklist functionality. Further enhancing your experience are syntax highlighting and line numbers courtesy of PrismJS, making your coding readable and accessible.
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Add-on stats

By: Blizz3
Daily users: 1,100
-5
Rating: 4.41
(17)
Version: 1.3.2 (Last updated: 2020-04-02)
Creation date: 2019-07-06
Weekly download count: 24
Firefox on Android: Yes
Risk impact: Moderate risk impact
Risk likelihood:
Low risk likelihood
Manifest version: 2
Permissions:
  • storage
  • <all_urls>
  • contextMenus
  • notifications
Size: 44.31K
URLs: Website

Ranking

# 2,940 ▼ 10
Other rankings
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Other platforms

Not available on Chrome
Not available on Android
Not available on Edge
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Add-on summary

Analyze keywords

Custom CSS Injector lets you write any CSS rules and apply them to any website you like. Change colours, backgrounds, resize and hide obtrusive elements. Anything you can do within the power of CSS! Simply write the CSS you want to apply in the provided text field and click 'Save' (NO page refresh required!). Apply the CSS to the URL, Domain or Globally by using the radio buttons provided. There is also a whitelist/blacklist functionality to govern which websites you'd like to apply the CSS to. Enjoy syntax highlighting and line numbers for code readability (Thanks to PrismJS!)

User reviews

These summaries are automatically generated weekly using AI based on recent user reviews. Firefox Browser Add-ons does not verify user reviews, so some user reviews may be inaccurate, spammy, or outdated.
Pros
  • Works great
  • Powerful and easy to use
  • Ideal for working in website backends
  • Lightweight and straightforward implementation
Cons
  • CSS inject timing is too late, affecting page load
  • Invalid data error when saving CSS rules
Most mentioned
  • Works great
  • Powerful and easy to use
  • Issues with CSS rule saving
User reviews
Fonction mais comment ajouter pour differents site ?
by Firefox user 17672785, 2024-11-19
by Firefox user 14033823, 2022-05-10
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Add-on safety

Risk impact

CustomCSS Injector requires a few sensitive permissions. Exercise caution before installing.

Risk impact analysis details
  • Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
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Risk likelihood

CustomCSS Injector has earned a fairly good reputation and likely can be trusted.

Risk likelihood analysis details
  • High This extension has low user count. Unpopular extensions may not be stable or safe.
  • Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
  • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
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