It's all about the tooling. I wrote my own for iommi where the html output of some code gets saved in a defined place, and then the finished documentation page embeds that html in an iframe. It's not only WAY WAY easier to maintain than a bunch of screenshots, but I found a ton of issues with the documentation after I made it so it runs all the examples and I can look at the output.
example: https://docs.iommi.rocks/en/latest/cookbook_forms.html
corresponding documentation/tests: https://github.com/iommirocks/iommi/blob/master/docs/test_do...
my evil hack to get this working: https://github.com/iommirocks/iommi/blob/master/make_doc_rst... and https://github.com/iommirocks/iommi/blob/master/iommi/docs.p...