then its the browser itself.. mozilla is one of the safest browser to use.
in this case, you have to add the host to the exception list para hindi na sya mafilter or choose another browser perhaps, and set the security to normal (or low?!)
is it safe? that i don't know and i can't be so sure.. but if you have a good anti virus/anti malware then it should at least help and lessen the threat.