Wrong IE mouseup checking in ui.core.js.
Limit mouseup out of window check to only versions of IE earlier than 9 as IE9 has this fixed.
This does not work. Are you using UI v 1.7?
Ah -- it does work! I updated to UI version 1.7, but then I realized that JQuery UI was loading the minified script. I updated the minified script, too, and now it works. I don't know if the UI version update was necessary.
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