Custom CSS rules Firefox

Custom CSS rules

By: sina
A Firefox extension to inject custom CSS into any website.
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Features & Capabilities

A simple Firefox browser extension that allows you to inject your own custom CSS rules into any website. Styles are saved per domain and applied automatically whenever you visit the site.

User Growth & Download Statistics

Manifest V3 Add-on
By:
sina
Daily users:
3
Version:
1.1 Last updated: 2025-04-04
Version code:
5921701
Creation date:
2025-04-01
Risk:
Moderate risk impact Moderate risk likelihood
Permissions:
Host permissions:
  • <all_urls>
Content scripts matches:
  • <all_urls>
Size:
96.85KB
Email:
ja*****@gmail.com
URLs:
Website
Full description:
See detailed description
Source:
Firefox Add-ons Store
Data ingested on:
2026-06-15
Compare stats and ranking:

Ranking

# 52,152 ▼ 357
Other rankings
#51 in rule keyword 8 ▼ 1#168 in custom font keyword 29 #169 in custom feed keyword 21 ▼ 2#180 in customer keyword 12 ▼ 2#229 in inject keyword 14 ▼ 1

For Developers

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Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
sina
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/custom-css-rules/
Email:
ja*****@gmail.com
Website:
https://sinajalalvandi.ir

Is Custom CSS rules Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Custom CSS rules 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.
  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Custom CSS rules is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

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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