Pass a top-level navigation initiator origin to Fetch

[bvandersloot-mozilla]

To un-logjam the cookie layering work, I've started whatwg/fetch#1807. That depends on this info to be piped into Fetch so we can actually specify in WHATWG what SameSite=Strict means.

This patch plumbs that through on top-level navigatable fetches.

This doesn't build because it relies upon the corresponding patch in Fetch. Let me know to land these.

• At least two implementers are interested (and none opposed):
  • Mozilla
  • Apple? (@annevk)
  • Google? (@johannhof )
• Tests are written and can be reviewed and commented upon at:
  • change is not observable, not needed?
• Implementation bugs are filed:
  • change is to update spec interfacing, not needed?
• Corresponding HTML AAM & ARIA in HTML issues & PRs:
• MDN issue is filed:
  • I don't think this is needed?
• The top of this comment includes a clear commit message to use.

(See WHATWG Working Mode: Changes for more details.)

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/browsing-the-web.html ( diff )
/infrastructure.html ( diff )

[annevk]

cc @johannhof

[annevk]

I think one thing we identified that's worth looking into here is what happens if OPENER opens POPUP and then attempts to navigate POPUP's EMBED using named targeting.

[annevk]

Please have a look at the formatting guidelines. This isn't quite it.

[bvandersloot-mozilla]

I'll take a crack at this while reading the style guide.

[bvandersloot-mozilla]

I think one thing we identified that's worth looking into here is what happens if OPENER opens POPUP and then attempts to navigate POPUP's EMBED using named targeting.

Looking into this, I think the only interesting case here is where OPENER is cross-origin to POPUP, because it is exactly this case where you have a non-ancestor initiator. This isn't possible to do because targeting is blocked by the cross-origin-ness of the opened window. We could test where OPENER and POPUP are same-origin, but that just feels like the existing iframe tests with extra steps. Let me know if you see anything worth testing here, but I don't see it.