Custom CSS

Custom CSS

Overwrite or inject custom CSS into website.

What is Custom CSS?
Custom CSS is a Firefox add-on that allows web developers and CSS experts to inject their own styles into any website, effectively customizing its appearance and overriding default styling.
By: Kenny Ooi
Users: 198 ▲ 9
Rating: 2.00 (4)
Version: 1.1 (Last updated: 2022-01-12)
Creation date: 2022-01-11
Weekly download count: 18
Firefox on Android: No
Risk impact: High risk impact
Risk likelihood: Low risk likelihood
Manifest version: 2
  • tabs
  • storage
  • http://*/
  • https://*/
Size: 27.77K
Stats date:

Other platforms

Not available on Chrome
Not available on Edge
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A simple plugin which allow web developer or those who familiar with CSS to inject own custom CSS into any website to overwrite default styling, such as font-size, font-color, and so on.

User reviews
Throws all kinds of errors for no reason, even with basic elements like #header. It doesn't have any formatting aids either, though I suppose if all you care about is size that's not a dealbreaker.
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Risk impact

Custom CSS is risky to use as it requires a number of sensitive permissions that can potentially harm your browser and steal your data. Exercise caution when installing this add-on. Review carefully before installing. We recommend that you only install Custom CSS if you trust the publisher.

Risk likelihood

Custom CSS has earned a fairly good reputation and likely can be trusted.

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