As observed already in another comment, I erred on the contenteditable attribute, that it’s not actually a boolean attribute like the best-known one disabled; r

As observed already in another comment, I erred on the contenteditable attribute, that it’s not actually a boolean attribute like the best-known one disabled; rather, it’s one of the handful of tristate attributes. But take one that’s actually a boolean attribute, and my remarks are completely correct. As for contenteditable, I’d still recommend writing `contenteditable` rather than `contenteditable="true"` (which two are equivalent).