Chapter 1: Components of Browser Extensions is an introductory chapter that outlines the core pieces of browser extensions and how they work together Manifest Background script Popup Options Content scripts Chapter 2: Extension Architecture covers in a more detailed way how an extension is actually built with manifest files, HTML, JS, and CSS Structure of Manifest, HTML, JS, CSS Differences between web apps and extension apps JS/HTML/CSS Bundling for deployment CRX files Chapter 3: Extension Manifests cover in detail the manifest.json file, which is the primary file that describes the extensions'' file layout, defines its permissions and behavior, and describes how it should appear in the browser. Components of the manifest Manifest v1, v2, and v3 Chapter 4: Background Scripts covers in detail the background script, which is the most important piece of the browser extension. It describes what they are capable of doing, as well as all the different ways they can be used for different types of browser extensions. Lifecycle Persistence Service workers Messaging relay between extension components Chapter 5: Content Scripts describes how extensions can insert code and styling into the actual page. It covers the myriad of ways in which this can be leveraged to completely customize any web browsing experience, as well as all the tricky pitfalls that users should be aware of. Injection and script lifecycle JS/CSS/Files Runtime/script sandboxing Shared DOM Special events (clicks) to open popup/similar Performance Chapter 6: Extension and Browser APIs is a reference chapter that goes through all the different APIs that browser extensions can use to change how the browser behaves. Overview of APIs (large list: https://developer.

chrome.com/docs/extensions/reference/) Storage Messaging Chapter 7: Permissions is a reference chapter that goes through all the different permissions that a browser extension can request. This is a sister chapter to Extension and Browser APIs, since using many APIs requires permissions for that API. Overview of permissions (large list: https://developer.chrome.com/docs/extensions/mv3/declare_permissions/) Required/Optional permissions Permissions changes Differences between v2 vs v3 Chapter 8: Networking covers all the different aspects of how chrome extensions can use and modify the browser''s network capabilities. This chapter also covers the important differences between webRequest and declarativeNetRequest. webRequest API declarativeNetRequest API Network requests in content scripts Network requests background scripts Network requests popup/options pages Browser credentials, cookies, and authentication Sniffing and intercepting traffic Chapter 9: Manifest v2 versus v3 covers the ongoing transition from manifest v2 to manifest v3.

This chapter is of critical importance in the next 18 months as browser vendors decide how to handle adblockers. Differences between v2 vs v3 Reasons for change Variable support between browsers Chapter 10: Browser modifications discusses interesting supplementary behaviors of browser extensions that allow for customization of various other parts of the browser. New tab page Developer console Chapter 11: Extension Deployment covers how to take code files and use them in the browser, both locally and in production. It also covers how release cycles and updates work in app stores. Install flow Local deployment Manual app store deployment Automated app store deployment Pushing and deploying updates Handling uninstalls Chapter 12: Building for different browsers covers the various idiosyncrasies between different browsers, as well as ways to have a single codebase be shared between multiple browsers. Chrome Firefox Edge Safari Chapter 13: Tooling and Frameworks covers all the ways that programmers can avoid developing browser extensions from scratch. This includes how it folds into existing frameworks, and also various open source tools that are useful for building browser extensions. Webpack Vue React CLI tools.