So I am really not sure about it.
I agree that empty end-tags (as opposed to end-tags with null names) should be disallowed, and further than leaving prefixes out of end-tags should be disallowed. After all, the attributes and content model depend just as much on the namespace name as on the raw element name. (I would argue for requiring all attributes to appear at both ends too, except that it's a pain in the ass.)
There is also a compromise: it can only be used for leaf elements
< to find it.
-
so <p>hello <b><i>W</>orld</b> !!! </p>
.
I am not sure that it would be good enough: it might cause frustration that if you want to add a
subelement of i, you have to close off that before adding the new one.
+1
