Sorry if this is OT. While trying to understand this error:
I learn from http://validator.w3.org/docs/errors.html that "'VI delimiter' is a technical term for the equal sign."
I'm all for precision, but I suggest it might be easier on the reader if the diagnostic read, "an attribute value literal can occur in an attribute specification list only after an equal sign." Would have helped me avoid that extra level of indirection.
It's only a nit. Even so, we don't often hear "will you please hurry up with that Aedes repellent!" :-)
I still don't grok why line 2913 produced the error.