While researching alternatives for this project I learned about Marionette. It looks as though that would be the raw/low-level way to interact with Firefox, but requires writing own frontend. It's something I want to come back to later when I have more time or more hands.

> Can you explain to me how to specify tests in a portable format, so I can help round out your tester without having to load all that dependency tree ?

If you are ok with me using this heathen tester concoction strictly as demolition scaffolding while I reduce mp-wp to its essentials then a spec written as Describe / It blocks would be really helpful. For example:

Describe: "Media Library"
It: "Can display a list of uploaded media in a table"
It: "Can upload a new item to the media library"
It: "Can view an item from the media library"
It: "Can edit an item from the media library"

etc...

If I had a list like that which covered all the parts of mp-wp you would like to keep around I could immediately get started on the grunt work of writing those tests. Once full coverage is achieved, I could then get to the more fun part of razing large sections of the codebase, confident that so long as the tests continue to pass we haven't accidentally blown up something useful.

After mp-wp is in a desirable state we simply abandon these tests all together, and think of a testing solution that doesn't involve Selenium, Java, and mess of assorted JS libs. I feel this is the fastest way to the desired outcome, and in this sense exploits the heathen tools without relying on them.

I don't know that/if anyone uses the selenium thing (or java, for that matter) -- I certainly never heard of it before. Can you explain to me how to specify tests in a portable format, so I can help round out your tester without having to load all that dependency tree ?