extension-functions-best-practices
Extension Functions Best Practices
Implementation guidance for browser extension features across 13 categories. Each category includes reference open-source projects and links to detailed implementation guides.
When to Use
- Building extension features in any supported category
- Looking for proven patterns and reference implementations
- Choosing libraries and APIs for specific functionality
- Understanding permission requirements
How Reference Projects Are Chosen
- Verifiable: Prefer projects you can install from a store, or build into a loadable extension from GitHub, with real Issues/Releases.
- Behavior-aligned: Table Highlights describe user-visible behavior (e.g. “merge HLS segments”) rather than only “call the downloads API”.
- Download / streaming: Tutorial-style
chrome.downloads+ anm3u8URL is often not enough for a playable file; treat rules/download.md (“Reality check & common pitfalls”) and repos such as Cat Catch, Live Stream Downloader, and Video DownloadHelper as the ground truth.
More from addfox/skills
addfox-best-practices
Best practices for building browser extensions with the Addfox framework. Use when developing extensions with Addfox, configuring manifest/entry/permissions, or when discussing MV3, cross-browser support, framework/styling choices, messaging, and content UI injection.
21addfox-debugging
Debug Addfox build and runtime issues, including terminal failures, manifest errors, extension loading issues, and context messaging problems.
18addfox-testing
Test Addfox extensions with Rstest for unit/component tests and Playwright for end-to-end extension loading.
17convert-web-pages-to-browser-extensions
Convert any frontend webpage into a browser extension entry page with an HTML entry. Supports popup, options, sidepanel, devtools, newtab, bookmarks override, history override, and custom entries. Use when the user asks to migrate or adapt an existing web page into extension UI.
7migrate-to-addfox
Migrate existing browser extensions from WXT, Plasmo, Extension.js/CRXJS, or vanilla setups to Addfox with incremental validation.
5