I'm running Firefox 56; my experience so far:
- from the top menu of Home page, only the Home button -the one with the ship's wheel- seems to work;
- the rest, "Upload / Log In /Sign Up" and "Home / Photos / Videos / ShipXplorer / Forum / Support / Contact" are dead;
- as for the Forum Topics, Top Categories, Latest Photo Comments and Latest Photos on Home page they do work, I'm prompted to the links when clicking them;
I'm writing this from Chrome, cannot log in on Firefox.
Update:
From the top menu, Home, Videos, ShipXplorer, Support and Contact buttons seem to be working now. Photos and Forum, and Log In buttons are still dead.