> That's one more reason not to rely on automated testing only.

I took an alternative conclusion - don't use shadow DOM or other bleeding edge tech when something much simpler will do. What ever happened to using document.getElementById? You can even skip much of this if you finish your work on the server before sending that text/html response...

I sometimes wonder if there's a huge thing I'm missing, but then I remember our customers love our product. Not a single one of them can tell that we don't use react or WASM. In fact, we have yet to receive a single complaint regarding our multipart form posts resulting in actual browser navigation. For whatever reason, the users don't seem to give a shit about this. It only ever seems to come up in the most ridiculous nerd conversations.