flXHR [flĕkʹsər],(flex-er)
is a *client-based* cross-browser, XHR-compatible tool for cross-domain
client-to-server ‚AJAX‘ communication. It utilizes an invisible
flXHR.swf instance that acts as sort of a client-side proxy for
requests, combined with a Javascript object/module wrapper that exposes
an identical interface to the native XMLHttpRequest (XHR) browser
object, with a few helpful additions and a couple of minor limitations.

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