firefox-extension-dev

Name: firefox-extension-dev
Availability: InStock
Author: acaprino

Develop Firefox WebExtensions with manifest.json and browser.* APIs.

6|2|Updated Jan 6, 2026

Search Tags:#developer tools #manifest.json #firefox #webextension #javascript api #browser extension

Ready to run

npx skills add https://github.com/acaprino/anvil-toolset --skill firefox-extension-dev

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: firefox-extension-dev
Source: https://github.com/acaprino/anvil-toolset/tree/main/plugins/browser-extensions/skills/firefox-extension-dev
Command: npx skills add https://github.com/acaprino/anvil-toolset --skill firefox-extension-dev

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

This Skill provides comprehensive guidance and reference material for developing, debugging, and publishing Firefox browser extensions (WebExtensions).

Core Features & Use Cases

Manifest File Guidance: Detailed explanations of manifest.json keys for both Manifest V2 and V3.
API Reference: A complete list and description of available browser.* APIs, including Firefox-specific features.
Development Workflow: Information on content scripts, background scripts, message passing, and native messaging.
Use Case: You need to create a new Firefox extension that modifies the appearance of web pages and communicates with a native application. This Skill will guide you through setting up the manifest.json, writing content and background scripts, and establishing native messaging.

Quick Start

Use the firefox-extension-dev skill to create a basic manifest.json file for a Manifest V3 Firefox extension.

Frequently Asked Questions about firefox-extension-dev

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I structure a manifest.json file for a Firefox WebExtension?▼

To structure a manifest.json file for a Firefox WebExtension, you define essential keys like background scripts, content scripts, and permissions. This Skill details both Manifest V2 and V3 requirements for building browser add-ons.

Can I use Firefox-specific JavaScript APIs like container tabs and sidebars in my extension?▼

Yes, you can use Firefox-specific JavaScript APIs like container tabs and sidebars in your extension. This Skill provides a complete reference for available browser.* APIs to facilitate building advanced WebExtension features.

How do I set up native messaging between a background script and a desktop application?▼

To set up native messaging between a background script and a desktop application, you establish a communication channel via the browser.* APIs. This Skill guides you through writing background scripts and configuring native messaging.

What is the best way to debug and publish a Firefox browser extension?▼

The best way to debug and publish a Firefox browser extension is by following the standard WebExtension development workflow. This Skill provides expert guidance on debugging scripts and navigating the publishing process for add-ons.

Does Firefox WebExtension development require different handling for content scripts versus background scripts?▼

Firefox WebExtension development requires distinct handling for content scripts, which manipulate web page appearance, and background scripts, which manage logic and events. This Skill explains how to implement and coordinate both script types.