`navigator.serviceWorker` may be undefined in some secure contexts

[TheCymaera]

lib Update Request

Configuration Check

My compilation target is ESNext and my lib is the default.

Missing / Incorrect Definition

navigator.serviceWorker is undefined in some secure contexts (private mode on Firefox), thus the correct type definition should be:

readonly serviceWorker?: ServiceWorkerContainer;

Sample Code

Bad:

navigator.serviceWorker.register()

Good:

navigator.serviceWorker?.register()

Documentation Link

https://developer.mozilla.org/en-US/docs/Web/API/Navigator/serviceWorker

[RyanCavanaugh]

APIs like these are marked non-optional for convenience, since it's extremely plausible that your script runs only in secure contexts as an invariant.

[FozzieHi]

@RyanCavanaugh I think this should be revisited. navigator.serviceWorker also may not be available in Firefox Private Windows.

The feature may not be available in private mode.

I think this makes it much more likely to have breakage go unnoticed rather than it just not being available in non-HTTPS contexts. Indeed I only came across this issue after experiencing such breakage on a public website.

[TheCymaera]

Similarly, navigator.share is not defined on MacOS Chrome in secure contexts.

[typescript-bot]

This issue has been marked 'Working as Intended' and has seen no recent activity. It has been automatically closed for house-keeping purposes.

[alex-eliot]

@RyanCavanaugh In Messenger's in-app browser, navigator.serviceWorker is undefined via HTTPS, no private mode. As @FozzieHi has said this is simply hurting developers by producing contradicting runtime behavior than what is suggested by TypeScript.