I keep forgetting that for the line break tag the slash is at the end instead of the beginning. <br> is the only tag like this.
There’s probably some theory around how the br tag is its own terminator or something, but it would save me a fair amount of re-editing my NPC dialogs if the other would just work also.
</tag> is the form of a closing tag, e.g. <b>bold text</b>.
<tag [attributes]/> is the form of an opening tag with nothing inside, equivalent to <tag [attributes]></tag>.
Making </br> work the same as <br/> is inconsistent with XML syntax, and ambiguous for strings which would put a </br> inside of a <br> label (it could close the label or be part of it). Allowing </br> isn’t a good solution, maybe &n; would be better, or just using the already valid (which is incredibly expressive).