Great article. Maybe a hot take but I think it's a good thing that dialog and details modify the DOM. It allows for UI state to be serialized and stored in a native way. I think input.value should work the same way too (although it's probably too late for that). Consider how some browsers will remember what you input into forms when you hit the back button: I think representing this as a cached version of the modified DOM makes a lot more sense than whatever magic browsers currently use to remember it. Many CSS pseudoclasses like :checked feel like a pre-attribute-selector bandaid.