100 Browser Extensions resources for developers

A battery-included framework that handles boilerplate for Manifest V3, including automatic HMR, React/Vue support, and simplified asset management.

A Vite-based framework designed for cross-browser compatibility, offering a unified API for Chrome, Firefox, and Safari builds.

Integrates extension development directly into Vite, enabling fast HMR for content scripts and service workers by updating the manifest dynamically.

A command-line tool for running, linting, and packaging extensions; essential for testing in Firefox and validating manifest structures.

A zero-config CLI for generating extension templates with Webpack, ideal for developers who prefer standard JavaScript/CSS without heavy frameworks.

A fast bundler based on esbuild; use it to bundle background service workers into a single file to avoid import issues in MV3.

A collection of Tailwind CSS components specifically sized for extension popups (300px-600px width) and side panels.

The 'browser' namespace polyfill by Mozilla that allows you to use Promise-based syntax in Chrome instead of callback-heavy 'chrome' APIs.

Use Zod schemas to validate your manifest.json and options storage at runtime to prevent crashes from unexpected user input.

Useful for testing content scripts against a wide variety of DOM structures to ensure your extension doesn't break host websites.

The mandatory way to handle DOM-dependent tasks (like audio playback or clipboard writing) that are no longer possible in service workers.

A new storage area in MV3 that keeps data in memory for the duration of the browser session; faster than storage.local.

The privacy-first replacement for webRequest; requires pre-defining rules in JSON for blocking or redirecting network requests.

Enables the persistent side panel UI introduced in Chrome 114, providing more screen real estate than traditional popups.

Techniques using chrome.alarms or dummy ports to prevent the service worker from terminating during long-running background tasks.

The MV3 method for injecting code into tabs; requires the 'scripting' permission and replaces the deprecated tabs.executeScript.

Use scripting.registerContentScripts to inject scripts based on user settings rather than hardcoding them in manifest.json.

Programmatically update the extension icon or badge text to show real-time status updates without the user opening the popup.

Communicating with a local desktop application via JSON-based stdin/stdout, bypassing sandbox limitations for heavy processing.

Configuring the 'content_security_policy' field to allow connections to specific API endpoints while complying with Web Store safety audits.

A low-code payment service designed specifically for extensions, handling subscriptions and one-time payments without a backend.

Accessing local Gemini Nano models directly through the browser (Chrome 127+) for on-device summarization and text generation.

A robust stack for multi-platform extensions; use Firebase to sync user license status across different browsers and devices.

Privacy-compliant event tracking to see which features users interact with most within the popup and content scripts.

Error tracking specifically configured for the extension environment to catch background service worker crashes before users report them.

A workflow for testing how your extension handles data migrations when upgrading from an old version to a new version locally.

Automate the upload and submission process to the Chrome Web Store and Firefox Add-ons using the 'chrome-webstore-upload' action.

Using Lemon Squeezy's hosted checkout to sell digital licenses for extensions, providing an alternative to Stripe for global tax handling.

Implementing a small Vercel/Cloudflare worker to proxy LLM requests, keeping your API keys out of the extension's client-side code.

A framework-agnostic way to handle localization beyond the basic chrome.i18n API, facilitating easier entry into international markets.