<span class="Apple-style-span" style="font-family: Arial, sans-serif; font-size: 13px; "><div style="margin-top: 0px; margin-bottom: 0px; ">When a page is loaded from an AppCache, even when online, external resources such as images will not be loaded at all.</div>
<div style="margin-top: 0px; margin-bottom: 0px; ">If <a href="http://foo.com">foo.com</a> has an image <img src="<a href="http://bar.com/img.png">http://bar.com/img.png</a>" />, then according to the steps in<br>
<div class="iu" style="margin-top: 0px; margin-bottom: 0px; color: rgb(80, 0, 80); "><a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/offline.html#changesToNetworkingModel" target="_blank" style="color: rgb(0, 101, 204); ">http://www.whatwg.org/specs/web-apps/current-work/multipage/offline.html#changesToNetworkingModel</a><br>
</div>it will fail the load for the resource.<div style="margin-top: 0px; margin-bottom: 0px; "><br></div><div style="margin-top: 0px; margin-bottom: 0px; ">For example, someone with an Offline Gmail client would never be able to see cross-domain images in emails, even when completely online.</div>
<div style="margin-top: 0px; margin-bottom: 0px; "><br></div><div style="margin-top: 0px; margin-bottom: 0px; ">There's no workaround in the current spec. For user-defined img tags, like those in webmail apps, the set of external domains is practically infinite. The NETWORK namespace, which requires a known domain for the domain-matching check, won't help. The FALLBACK namespace has to have a known domain, that has to be the same as the manifest's domain, so it also can't help.</div>
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