# HTML, CSS, JS Validator

> The utility checks and fixes HTML, CSS, and JavaScript errors on websites.

Canonical page: [https://chrome-stats.com/d/html-css-js-validator](https://chrome-stats.com/d/html-css-js-validator)

## Overview

- **ID:** `html-css-js-validator`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** Martin Sullivan
- **Category:** web-development,search-tools,tabs
- **Daily users:** 1
- **Rating:** 1.00 / 5 (1 ratings)
- **Version:** 1.0
- **Last updated:** 2024-09-11
- **First published:** 2024-09-10
- **Size:** 15 KB
- **Data as of:** 2026-09-06
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/html-css-js-validator/)

## Description

The utility checks and fixes HTML, CSS, and JavaScript errors on websites.Upgraded function: Display detailed errors in popup interface, Automatically fix some common errors, Create error reports, Suggested fixes

## Rankings

- #87,793 — Overall
- #143 — html

## Permissions and access

### Permissions

- `activeTab`
- `storage`
- `webRequest`
- `webNavigation`

### Content script matches

- `<all_urls>`

## Safety

- **Risk impact:** High 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/html-css-js-validator)