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[OPEN]missing support for xdomainrequest in IE
Why don't you support xdomainrequest in IE which was implemented 2 years ago?
It's something we'll look into. You can do CORS requests in other supported browsers (Safari 4, Firefox 3.5) however they come with a series of caveats that need to be pointed out.
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Don't be afraid of the source code!
+1 for XDomainRequest object support.
IMHO, it seems like this should be a higher priority feature request for ExtJS since it's so common to use it for making "in-browser client apps" that, arguably, should be able to easily POST/GET to any server (just like a desktop app).