If your app is running in Firefox, presumably it's actually written properly to standards Unfortunately, as I learned in 10 years of corporate consulting work,

If your app is running in Firefox, presumably it's actually written properly to standards Unfortunately, as I learned in 10 years of corporate consulting work, that presumption isn't entirely true. The typical corporate webapp I've encountered was written to the corporate browser standard du jour, with very little attention paid to standards. It likely has poor unit test coverage and absolutely no automated testing of client-side markup or code. High profile apps are likely to be an exception - I recently worked on software that delivers market data to the people making billion-dollar trades. It's top notch and awe-inspiring in every respect. But for every one of these, there are 100 apps that let you change your insurance plan, submit new automated deposit instructions, request vacation time, check inventory levels, etc. All done on the absolute cheap by developers whose true skill set is usually integration with legacy ERP software. The devops folks are right to be wary of a new browser deploys in such an environment.