First of all, let's welcome firefox to the unwanted browsers category. It seems that with each new version, firefox is taking a step backward.
Now that the party is over, let's talk about the problem.
If you use the full size map (Resize the map option - top right corner of the map), you wont the able to click on any of the option on top of the map ( categories icons - search box - marker center - get directions - etc )
Tested with the new firefox version: 14.0, and the hotspots demo page: http://demo.compojoom.com/hotspots