Things are only getting worse in this regard as more and more devs don't even test on FF, and FF lags behind new features. Internal business apps are going to be Chrome only and it's only downhill from there.
> They are trying to stop unmonitored exfiltration of data.
This was always a pipe dream (preventing data exfiltration). The best any company do is to prevent accidental exfiltration of data. Like when someone attaches a spreadsheet with social security/credit card numbers to an email going out over the Internet. There's tools to detect that sort of thing (and stop it) but they don't work when the data is encrypted.
There currently exists no technology that can stop the human problem of data exfiltration. Here's a quick quiz to see if anyone in your company can exfiltrate whatever TF they want: Can employees play sounds on their desktop (as in, it emits sound)? Then they can exfiltrate any file they have read access to pretty damned quickly. Even huge, multi-gigabyte files!
Current data exfiltration methods can take advantage of a tiny corner of a monitor, the sound output (direct connect to line out or optical is ideal!), power lines (yes, this works! https://www.helpnetsecurity.com/2018/04/13/data-exfiltration...), various USB tricks (even if entire categories of "storage" devices are blocked via software), and many, many more. Most of them are basically undetectable as well and can be executed with JavaScript in any browser that gives the user access to the developer console.
Obviously, if end users have access to PowerShell or Python that's even faster/better at exfiltrating the data.
My favorite one though has got to be the sound output... You can write a simple script that converts bits into inaudible sounds that can be picked up by a cell phone in your pocket! It's not nearly as fast as a direct connection to the line out jack but it is so cool! haha
Second place has to be data exfiltration, "by blinking the numlock LED"
