Well, if we’ re following my logic, like you claim, then it depends on why the page is failing to load in Firefox: Are you using an outdated version of Firefox or on an outdated system? Is Firefox missing major functionality? Has your admin disabled major functionality in Firefox? Won’t some part of the website load in Firefox and if so, why? Are you using assistive technology in Firefox and if so, is it broken, misconfigured, or does the website not follow best practice?
If it is for another reason, then it obviously depends on that reason