Brotli Header Lab

Follows Accept-Encoding from your browser through each Cloudflare hop. Each arrow shows what a hop sent. Each box shows what the next hop received. A red arrow means Cloudflare changed the header in between.

The setting changes what the Pages Function and the Worker send onwards. Your browser's own header can't be changed from a web page. Each onward request goes back through Cloudflare's edge, which rewrites Accept-Encoding to gzip, br again. That's why those arrows turn red.