PNA Permission Prompt with Service Worker

[DanielBaulig]

Since a fix for #126 was shipped in Chrome earlier this year, PNA Permission Prompt seems to no longer work for applications being served from a Service Worker.

It seems like that the mixed content policy kicks in, even when targetAddressSpace: 'private' is provided to the fetch call from the main document. Example

It's not entirely clear to me if this is expected as part of the aforementioned fix or not. It seems like the fix applies some changes to how the main document's address space is calculated, but it doesn't appear like that should affect the sub-resource address space and mixed content check. But then again, my understanding here is lackluster at best.

In either case: I was wondering if there are any plans or ideas on how to re-enable support for PNA Permission Prompt requests from documents that were served via a Service Worker? Ironically, the fix to the issue I reported fully broke the IOT device management application I worked on.

I was wondering if the Static Routing API could maybe be used to in the context of the mixed content policy check such that routes that have been explicitly flagged to bypass Service Workers could at least be allowed to continue?

https://developer.chrome.com/blog/service-worker-static-routing-api-origin-trial
https://github.com/WICG/service-worker-static-routing-api

Any thoughts?