When caret is on a namespace declaration, Ctrl-Shift-F7 highlights the "location" part of the matching "xsi:schemaLocation" pair, but not the current element.
This is really a "beyond trivial" issue, since there probably will never be another reference a given XML file.

Still, it would be more consistent if:

• current element (namespace part of namespace declaration) would be highlighted (using "write/definition" location)
• the namespace part of the matching "xsi:schemaLocation" pair would be highlighted (instead of the location), since logically that is the part the refers to the namespace

See attached screenshot. Caret marked with black bar.