Normalize the tag with trailing '/' character (such as `<img ... />`).

        The trailing '/' character has no effect on void elements, but on
        foreign elements it marks the start tag as self-closing.

        .. seealso::
           `HTML5 - Start tags
            <http://www.w3.org/TR/html5-author/syntax.html#syntax-start-tag>`_

def handle_startendtag(self, tag, attrs):
        """
        Normalize the tag with trailing '/' character (such as `<img ... />`).

        The trailing '/' character has no effect on void elements, but on
        foreign elements it marks the start tag as self-closing.

        .. seealso::
           `HTML5 - Start tags
            <http://www.w3.org/TR/html5-author/syntax.html#syntax-start-tag>`_
        """
        is_foreign = tag not in _VOID_ELEMENTS
        self._append_tag(tag, attrs, closing=is_foreign)
        if tag in _BLOCK_ELEMENTS:
            self._enter_newline()
        elif tag not in _HIDDEN_ELEMENTS:
            self._reset_newline_status()