docs: clarify HTML validator warnings for Vue-specific directives #3264
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What This Does
This adds a tip box to the
template-syntax.mdguide explaining that Vue-specific attributes likev-if,@click, andv-bindmay appear as invalid in HTML validators or IDEs. These are Vue template directives and are expected to be handled by Vue's compiler.Why
Fixes vuejs/vue#4428, which notes that new users may find these attributes invalid when writing Vue templates. This update clarifies that this is expected behavior and not a bug.
Thanks!