Widgets no longer working after upgrading to 2.8
You may have noticed that your widgets no longer work after upgrading to WordPress 2.8.
This issue was brought to my attention a few days ago by a client who upgraded and then found they could no longer edit, add, or delete widgets. After toying around with things, I found the solution:
Deactivating plugins that use their own version of the standard WP Script files (jQuery, jQuery UI, Scriptaculous, etc). In my clients case, this meant deactivating the Google SEO Positioner plugin.
This was simply trial and error. I deactivated plugins using JS files one-by-one, checking widgets after each time. If it didn’t help, I re-activated the plugin and went to the next one.
Since not all plugins use JavaScript, I was able to find the culprit quickly.
Hope this helps someone out there 
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