I started to use Mozilla FireFox from about a week, everithing is just fine (Instead that DashBoard button doesn/t work) but a few days ago when I go to my Inbox & press delete messages or Move nothing happens.
When I open JavaScript Console there is a following errors:

Error: FournierTransformationDeleteMethod is not defined
Source File: http://www.levelextreme.com/Javascript/List.js
Line: 91

Is there a settings in FireFox that I missed to make this buttons start working or this is bacause something is changed over the UT?

TIA