Compression dictionary transport is a relatively new feature in HTTP that allows for using custom compression dictionaries to improve the compression of HTTP responses. For more background on compression dictionary transport I recommend reading the web.dev article on the topic and watching my video from the performance.now() 2023 conference. If a given request comes in with a Sec-Fetch-Dest: document request header, then I add Link headers for all of the configured stand-alone dictionaries. For the Use-As-Dictionary header, the worker needs to identify relevant responses and add the dictionary header with appropriate instructions to each one. Next stepsIt’s worth noting that compression dictionary transport is not specific to browsers and the web.