1. go here: https://people.mozilla.org/~ewong2/push-notification-test/ 2. unregister if SW already exists and refresh 3. select sw-focus-bug.js then install, subscribe, then xhr 4. click on the notification actual: you should see a TypeError caught or printed to browser console. expected: no exception

spec says: https://slightlyoff.github.io/ServiceWorker/spec/service_worker/#clients Let url be the result of parsing url with entry settings object's API base URL. If url is failure, return a promise rejected with a TypeError. If url is about:blank, return a promise rejected with a TypeError. If this algorithm is not allowed to show a popup, return a promise rejected with an "InvalidAccessError" exception.

William said he'd get to this so assigning to him.

This bug looks invalid. The test script has a couple bugs, I get a reference error after clicking on the notification and the script also calls client.focus with a URL argument, but that function doesn't take a URL argument. The steps you have listed in comment 1 are from the openWindow algorithm but the script doesn't call that anywhere. We do return TypeError for invalid URLs: http://hg.mozilla.org/mozilla-central/file/c5cb194cc9cb/dom/workers/ServiceWorkerClients.cpp#l733 http://hg.mozilla.org/mozilla-central/file/c5cb194cc9cb/dom/workers/ServiceWorkerClients.cpp#l582 I tested this by trying to openWindow on "about:blank" and an invalid URL ("http://[invalid"), in both cases I got TypeError.