it's related to adblocker, i eventually disabled adblock for that website, but without disabling it it wont work. i know it's not directly a firefox issue, but with mobile chrome not having adblocking it kinda is in that they don't care. it honestly took me to long to figure it because i could not believe that a multi national bank would have this broken website (and that is with new 2018-19 redesign). it's not the first website to not work without js, but you would assume that the bank website would be done in a way where if analytics is not loaded the rest of the webpage would continue to work.