I got it there is new 3d layer option...

Hi,

This is the simples option, not always help but we encourage to try. 

- Copy and paste in address bar about:support  
- Select following http://nimb.ws/Vm5pjy 
- Rename this folder to any name and restart Firefox http://nimb.ws/awxfuW BUT don't delete it. Just rename it, for example Storage_OLD

If it won't help, let us know.

Also, if you don't see welcome message but settings get rest, that will be fixed next update soon.