At this moment, we haven't had any platform wide issues in relation to Firefox. This may be a local issue. Does the issue persist when accessing Firefox from another device or can you please try accessing this on an incognito Firefox browser please?
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Could be a local problem. It didn't work with an incognito tab. I noticed it flashes a 500 error before going back to the login page and sometimes a 504 bad gateway error. FF version 118.0.2(64bit) Win10 Pro