Improvement: Jade

[im-n1]

With a bit of modification, you can add Jade syntax hilight.

Original syntax/vue.vim

  9 syntax include @HTML syntax/html.vim
 10 unlet b:current_syntax
 11 syntax region template keepend start=/<template\( lang="[a-zA-Z]\+"\)\?>/ end="</template>" contains=@HTML fold

With Jade support:

  9 syntax include @HTML syntax/html.vim
 10 unlet b:current_syntax
 11 syntax region template keepend start=/<template>/ end="</template>" contains=@HTML fold
 12 
 13 syntax include @JADE syntax/jade.vim
 14 unlet b:current_syntax
 15 syntax region template keepend start=/<template lang="jade">/ end="</template>" contains=@JADE fold

Peace.