HTML: top-level data: URLs

[annevk]

What is the exact behavior that we want here?

Firefox behavior of closing the popups makes some sense to me and could be explained through COOP. In that the data: URL acts as if it creates a new browsing context group (which we then error and leave up to the user agent to figure out UX for).

cc @cdumez @mystor @natechapin @domenic @mikewest @JuniorHsu

[annevk]

Any other scenarios that might need tests?

[mystor]

Any other scenarios that might need tests?

We should probably also test with window.open("...", "", "noopener"); as well as using <a href="..." rel="{opener,noopener}">

[annevk]

I did for window.open(). It seems hard to create pass conditions for <a>.

@jgraham does WebDriver allow you to make assertions about the number of open tabs and what URLs they point to?

[jgraham]

It does, but I don't think our testdriver abstraction exposes the list of window handles or provides the ability to switch to another window. So implementing this at the moment would be quite a bit of work.

[annevk]

@domenic @ParisMeuleman @hemeryar what do you think?

[domenic]

I'd like to defer to @ParisMeuleman @hemeryar, who are much more in the guts of our COOP/popup code and spec space than I am at the moment.

[annevk]

To be clear, this isn't really about COOP, this is mostly about navigating to data URLs in a top-level browsing context failing (and if these tests seem okay, adding a corresponding change to the HTML Standard).

[ParisMeuleman]

Sorry for the delay here... those changes make sense to me, thanks for adding those!
But I must admit that I'm not well versed in data urls!

[annevk]

Thanks, created whatwg/html#5279 to complement this.