Mobile menu on Firefox Android phone not working.

I have seen two topics with this issue and no resolution. I have picked up this site for administration and looks like this was probably an issue at install, but since the person installing had an iPhone, it was never tested. But even if you check mobile view in the settings, the mobile menu is blank white, but works on an iPhone. Has anyone else tested Firefox with an android phone getting a blank white screen when clicking the menu and what did you do to resolve it?

Thanks in advance

The page I need help with: [log in to see the link]