It appears to be a problem with Greasemonkey. See this blog for suggestions: http://www.blogger.com/comment.g?blogID=11645460&postID=1135985267118422...
Josh Gordon wrote:
When I try to run this script (in any incarnation), I get nothing on my Firefox (OS X, Firefox 1.5, monkey 0.6.4), but my Javascript console says:
Error: Config is not defined Source File: file:///Users/Josh/Library/Application%20Support/Firefox/Profiles/u4f2twek.default/extensions/%7Be4a8a97b-f2ed-450b-b12d-ee082ba24781%7D/components/greasemonkey.js Line: 117
Any idea how to fix this?