CSS/JS Inject
By: Freiholtz
Inject your custom CSS/JS to any page.
WARNING: adding styling and script to a page can break its functionality and make it unsafe and break terms so use on your own risk and with good judgment preferably on your own sites.
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Features & Capabilities
User Growth & Download Statistics
Manifest V2 Add-on
- By:
- Freiholtz
- Daily users:
- 59 2
- Rating:
- 5.00 (2)
- Version:
- 0.1.1 Last updated: 2025-04-01
- Version code:
- 5921880
- Creation date:
- 2025-02-04
- Risk:
- High risk impact Moderate risk likelihood
- Permissions:
- Content scripts matches:
- <all_urls>
- <all_urls>
- Size:
- 120.39KB
- Full description:
- See detailed description
- Source:
- Firefox Add-ons Store
- Data ingested on:
- 2026-06-14
- Compare stats and ranking:
- CSS/JS Inject vs CSS and JS Injector
- CSS/JS Inject vs Custom CSS/JS Injector
- CSS/JS Inject vs Code Inject
Ranking
For Developers
Contact the developer
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User Reviews
Nice extension, easy to use, scripts are saved per page which is what I needed and the scripts run at page content load (ig on DOMContentLoaded event)
by Ya*****, 2025-07-01
Is CSS/JS Inject 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.
CSS/JS Inject requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.
Risk impact analysis details
- Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
- Critical ****** ****** ** *** ********* ****** * *********** ******** **** ** ** *** ******* *** ****** **** **** *** ******* *****
- 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.
CSS/JS Inject 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 **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
- Good **** ********* *** **** **** *******
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