activate() should fulfill even if the inner document load failed due to DNS/x-frame-options etc etc

[jakearchibald]

Only just occurred to me that iframes fire their load event even in the case of navigation 'failures'. If we reject in similar cases we're revealing something new.

[domenic]

This is somewhat contentious and non-interoperable, actually; see whatwg/html#125, whatwg/html#1230, and whatwg/html#4247.

[jakearchibald]

Hah, perfect. I guess we should just do whatever the spec does right now, and change whenever the spec changes.

[jeremyroman]

It will certainly be observable to them that they weren't unloaded. Unlike the load event, activate does commit them to going there if it did succeed in loading and so is less useful for passively observing XFO etc than <iframe onload>.