Compressing data before writing it to IndexedDB or sending it over a slow connection is a real optimization. When a cached API response is too large for reliable storage, or when you need to shrink a JSON payload before POSTing it, pako.gzip() is the standard reach. But pako is a pure-JavaScript port of zlib — written in user space to fill a gap the browser had at the time. The CompressionStream API is that gap closing. The API CompressionStream is a transform stream — da...