Dynamically changing favicons with JavaScript. I just spotted GitHub using this trick to swap out the favicon on a pull request that hadn’t passed its tests yet for github.com/favicon-failure.ico with a little cross icon in the corner.
Recent articles
- Adding dynamic features to an aggressively cached website - 28th January 2026
- ChatGPT Containers can now run bash, pip/npm install packages, and download files - 26th January 2026
- Wilson Lin on FastRender: a browser built by thousands of parallel agents - 23rd January 2026