jfc. I don't have anything to say to this other than that it deserves calling out.

> You've never seen (or implemented) an A/B test where the test was whether to improve the way e.g. the invoicing software generates PDFs?

I have never in my life seen or implemented an a/b test on a tool used by professionals. I see consumer-facing tests on websites all the time, but nothing silently changing the software on your computer. I mean, there are mandatory updates, which I do already consider to be malware, but those are, at least, not silent.