Separate from the large number of accessibility issues in jdwp-protocol.html, there is an HTML error (the one remaining HTML error in all the generated documentation.

DocCheck reports (via tidy):

build/linux-x86_64-server-release/images/docs/specs/jdwp/jdwp-protocol.html:14:1: Warning: <h1> attribute "id" has invalid value "Protocol Details"

Space characters are not allowed in the value of an "id" attribute.