demo · v140

Cache Flow

Where a fetch issued by a blob-loaded SharedWorker actually goes. Pre-140 it bypassed the service worker entirely; post-140 it flows through the SW like any other request. Pick the Chrome version to see the corresponding route.

pre-140 140+ 
// Before 140
//   blob worker → network (SW bypassed) → server → response
//
// After 140
//   blob worker → fetch event → SW caches.match → cache hit (or network)

why this matters

Blob-URL workers are a common idiom: ship the worker source inline in your bundle rather than as a separate .js file. Pre-140, those workers couldn't benefit from your offline cache because the SW didn't see their fetches. Post-140 they share the SW with the page. The change closes the "why doesn't my Workbox cache work for my worker traffic?" bug class.

see also