This article appeared originally on Mozilla Marketing Engineering & Operations blog

The Snippets Service allows Mozilla to communicate with Firefox users directly by placing a snippet of text and an image on their new tab page. Snippets share exciting news from the Mozilla World, useful tips and tricks based on user activity and sometimes jokes.

To achieve personalized, activity based messaging in a privacy respecting and efficient manner, the service creates a Bundle of Snippets per locale. Bundles are HTML documents that contain all Snippets targeted to a group of users, including their Style-Sheets, images, metadata and the JS decision engine …

https://giorgos.sealabs.net/using-brotli-compression-to-reduce-cdn-costs.html