'FetchEvent.handled' is a new service worker API which is added in spec as following:
spec PR: https://github.com/w3c/ServiceWorker/pull/1496
It's good to support this as it notifies developers when fetch event is processed.
Note that this is support in Chrome and Firefox since late 2020:
Created attachment 448760 [details]
Submitted web-platform-tests pull request: https://github.com/web-platform-tests/wpt/pull/32311
This patch modifies the imported WPT tests. Please ensure that any changes on the tests (not coming from a WPT import) are exported to WPT. Please see https://trac.webkit.org/wiki/WPTExportProcess
Comment on attachment 448760 [details]
Committed r287915 (245948@main): <https://commits.webkit.org/245948@main>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 448760 [details].