# browser-addon-custom-js

> to run custom JS on any website, instead of having to run a bookmarklet every time i visit a page very experimental - please only use JS you can trust

Canonical page: [https://chrome-stats.com/d/browser-addon-custom-js](https://chrome-stats.com/d/browser-addon-custom-js)

## Overview

- **ID:** `browser-addon-custom-js`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** Howard Chiam
- **Category:** web-development
- **Daily users:** 3
- **Weekly downloads:** 1
- **Version:** 1.1.1
- **Last updated:** 2023-07-01
- **First published:** 2023-06-30
- **Size:** 14 KB
- **Data as of:** 2026-09-05
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/browser-addon-custom-js/)

## Description

browser-addon-custom-js is an experimental Firefox add-on that allows you to run custom JavaScript on any website. With this add-on, you can easily execute your trusted JavaScript code instead of relying on bookmarklets every time you visit a page. Take control of your browsing experience with browser-addon-custom-js.

## Rankings

- #55,582 — Overall

## Permissions and access

### Permissions

- `storage`
- `unlimitedStorage`

### Content script matches

- `*`

## Safety

- **Risk impact:** Moderate risk impact
- **Risk likelihood:** Moderate risk likelihood

### Analysis details

- Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
- 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/browser-addon-custom-js)