But if you are calling somebody or something "professional" what you are saying is they act as if they were doing it in a certain way. If they don't follow the practices it does not matter if they are doing it for free.
It is like saying a kid is doing something professionally (even if he is not) and argumenting that it is because he isn't paid for it.
I mean I fail to understand what are you trying to say, someone stops being a professional as soon as it hasn't covered a test case?
Or are they kids just for having slipped a bug? Despite their work powers a lot of companies software (including the ones I work for)
Are you just trolling?
I don't know if they are or are not professionals.
It is just my opinion that being nice and prompt about removing cause of the damage after they have caused damage through recklessly ignoring industry standards cannot be reason to call their entire set of actions around this particular issue as "professional".
So they didn't say their "entire set of actions" was "professional" just that it was disclosed and resolved professionally.
If you consider that kind of behavior recklessly unprofessional I'd be amazed to see the kind of tests you write for your code.