Just downloaded Firefox. Same problem.

Clicked on Tools, then Error Console, & got a load of warnings with errors....?

The errors (about 7 or 8) all say, Permission denied to call method location to.string.
The warnings, of which there are a lot, say
Error in parsing value for property 'cursor'. Declaration dropped.
Expected ':' but found '.'. Declaration dropped.
Error in parsing value for property 'background-repeat'. Declaration dropped.
etc. etc.

Any ideas what this gobble-de-gook means?

BiLL