The \href{URL}{text} command of the hyperref package doesn't get scoped correctly, I think. URL receives the following scope:
text.tex.latex meta.group.braces.tex meta.reference.label.latex constant.other.reference.lable.latex
Shouldn't it rather receive:
text.tex.latex meta.group.braces.tex meta.function.link.url.latex markup.underline.link.latex
Small thing, I know, but it affects syntax coloring and it means that you cannot launch the URL with ⌅.
Best, Mark