With the arrival of jQuery 1.9, I have updated Impromptu to remove IE 6 specific code. This happens to be the only browser specific code, fortunately. These were the only changes, mostly in preparation of the upcoming jQuery releases. You can check out the documentation or grab the new version from Github.
Also if you're interested in learning more about using advanced features of Impromptu check out the eBook "Impromptu from I to U".
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