# Custom CSS

> Overwrite or inject custom CSS into website.

Canonical page: [https://chrome-stats.com/d/qb-custom-css](https://chrome-stats.com/d/qb-custom-css)

## Overview

- **ID:** `qb-custom-css`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** Kenny Ooi
- **Category:** web-development,appearance
- **Daily users:** 740
- **Weekly downloads:** 26
- **Rating:** 4.29 / 5 (7 ratings)
- **Version:** 1.1
- **Last updated:** 2022-01-12
- **First published:** 2022-01-11
- **Size:** 27 KB
- **Data as of:** 2026-09-14
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/qb-custom-css/)

## Description

**Custom CSS** is a straightforward Chrome extension designed for web developers and CSS enthusiasts. It empowers users to inject their own custom CSS into any website, allowing complete control over the site's appearance by overwriting default styles such as font size, font color, and other visual elements.

This extension enhances user experience by providing a flexible tool to personalize or test website styles dynamically without modifying the site's source code. Whether you want to improve readability, tweak design details, or experiment with styling, Custom CSS offers an easy and efficient solution to customize websites on the fly.

## Rankings

- #3,995 — Overall
- #7 — custom font
- #8 — custom feed
- #9 — customer
- #38 — inject
- #42 — customize

## Permissions and access

### Permissions

- `tabs`
- `storage`
- `http://*/`
- `https://*/`

### Content script matches

- `*`

## Safety

- **Risk impact:** High risk impact
- **Risk likelihood:** Low risk likelihood

### Analysis details

- Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

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Source: [Chrome-Stats](https://chrome-stats.com/d/qb-custom-css)