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<b><a class="bz_bug_link
bz_status_NEW "
title="NEW - Scripts with protocol-relative URLs fail to load in about:blank"
href="https://bugs.webkit.org/show_bug.cgi?id=145692#c2">Comment # 2</a>
on <a class="bz_bug_link
bz_status_NEW "
title="NEW - Scripts with protocol-relative URLs fail to load in about:blank"
href="https://bugs.webkit.org/show_bug.cgi?id=145692">bug 145692</a>
from <span class="vcard"><a class="email" href="mailto:x@jx0.co" title="Jon <x@jx0.co>"> <span class="fn">Jon</span></a>
</span></b>
<pre>My understanding is that about:blank is not a valid "fallback base URL", and the behavior described by the HTML spec involves tracing back through parent browsing contexts until a non-about base URL is found.
<a href="https://html.spec.whatwg.org/multipage/infrastructure.html#fallback-base-url">https://html.spec.whatwg.org/multipage/infrastructure.html#fallback-base-url</a>
Since the address of the inner iframe is "about:blank", to find the fallback base URL, we take the document base URL of its creator browsing context (the outer iframe).
The document base URL of the outer iframe is just its fallback base URL, which likewise, is the document base URL of the top browsing context.
So when parsing the protocol-relative URL of the script tag inside the inner iframe, we should be using the base URL of the top window in this case (and therefore deriving the proper scheme from there).</pre>
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