I did a little song-and-dance that sets up Puppeteer , takes screenshots of your app (like, all the routes you care about), and then compares them to the “golden” ones. If they match, your test passes!
It only works with Chrome (because Puppeteer), but that's not a big deal since this is the kind of thing you only put in your
devDependencies. The results are super cool in your test suite output: