IE9+ has no issue with all the ECMA JS. I used compat inspector (http://blogs.msdn.com/b/ie/archive/2012/01/20/ie10-compat-inspector.aspx) and found that code sniffing is causing the trouble.
To confirm that the problem is with the library, In edit_area_full.js, change the line:
isIE=(navigator.appName=="Microsoft Internet Explorer")
to
isGecko=(navigator.appName=="Microsoft Internet Explorer")
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Bad idea, kills the caret on all browsers so you can't see where you're typing.
IE9+ has no issue with all the ECMA JS. I used compat inspector (http://blogs.msdn.com/b/ie/archive/2012/01/20/ie10-compat-inspector.aspx) and found that code sniffing is causing the trouble.
To confirm that the problem is with the library, In edit_area_full.js, change the line:
isIE=(navigator.appName=="Microsoft Internet Explorer")
to
isGecko=(navigator.appName=="Microsoft Internet Explorer")
and run it in IE9 or IE10.
The EditArea code is highly based on Browser versions (isIE, isOpera...). Rather using browser check, please use feature detection techniques. See http://blogs.msdn.com/b/ie/archive/2010/04/14/same-markup-writing-cross-browser-code.aspx and http://msdn.microsoft.com/en-us/library/ie/hh273397\(v=vs.85).aspx
Also
IE 10 removes the legacy DX Filters. http://blogs.msdn.com/b/ie/archive/2012/06/04/legacy-dx-filters-removed-from-ie10-release-preview.aspx
Please use Opacity and standards effects in CSS/JS for IE10.