I Cannot use my bank's bill pay. The bank's IT says that since the last Firefox update it's no longer compatable

If someone (ideally your bank's IT) reports it to bugzilla, and if they know why, even better, ideally with some reduced testcase, then it's possible.

If nobody knows about it, the chances get smaller.

Thanks, I contacted the bank & told them, I guess we wait.

You can also submit the page giving you any errors with the built in "Report Broken Site" functionality from the browser menu — describing the feature that isn't working for you, to help surface the issue to the engineers. (In case somebody uses the same bank, they might be able to get to the bottom of it.)