Mixed Content: express UI requirements imperatively

[annevk]

It would help if the allow/deny algorithms Fetch invokes also indicate what happens to the UI. See w3c/ServiceWorker#119 (comment) and previous comments for some of the confusion not having this caused. (Apart from the general difficulty of reading all these specifications.)

[mikewest]

UI is generally something that we're not trying to specify, other than in fairly broad strokes. What is it specifically that you'd like to see hooked via Fetch (there are lots of questions in that thread...)?

[annevk]

That even though something is allowed to be fetched (or retrieved from the Cache API), mostly due historical incompetence of browsers and network effects, a Mixed Content SHOULD be displayed somewhere.

[annevk]

You can now use "request's window" for this.