drupal_pre_render_html_tag() is not specific in allowing which tags can be void (no closing tag).
Only allow void elements to have no closing tag.
User interface changes
Original report by @samj
Please add support for the rel=shortlink standard so as clients can auto-detect the short links rather than having to manufacture their own.
Beta phase evaluation
|Issue category||Bug because elements that are not intended to self-close, do if their value is empty.|
|Issue priority||Major because it causes unintentional markup bugs.|
|Prioritized changes||The main goal of this issue is DX and TX for markup generation|