[Service Worker] Termination policy Service workers don't always get terminated as one would expect. Steps to Reproduce: 1. Load <https://mdn.github.io/sw-test/> 2. Navigate to <https://webkit.org> => Service Workers <https://mdn.github.io/sw-test/sw.js> is still alive Relatedly, currently just reloading a page with a service worker causes a new service worker to spawn: Steps to Reproduce: 1. Load <https://mdn.github.io/sw-test/> 2. Reload 3 times => Multiple Service Workers exist for <https://mdn.github.io/sw-test/sw.js> Both cases can result in a large list of Service Workers show up as inspector debug targets, and when there are duplicates it is unclear which is the active worker.