Markdown parser crashes on emphasized text in deleted text in list item

[sebix]

This markdown text:

 * <del>Deleted list item with _emphasized text_</del>

causes the following exception:

2025-02-12 16:54:11,193 ERROR moin.items.content:316 An exception happened in _render_data (error_id = 08f9c665-393d-4890-94d7-e67430dc4e7f ):
Traceback (most recent call last):
  File "/home/sebastianw/dev/moin/src/moin/items/content.py", line 304, in _render_data
    doc = self.internal_representation(preview=preview)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sebastianw/dev/moin/src/moin/utils/clock.py", line 65, in wrapper
    retval = f(*args, **kw)
             ^^^^^^^^^^^^^^
  File "/home/sebastianw/dev/moin/src/moin/items/content.py", line 260, in internal_representation
    doc = input_conv(preview or self.rev, self.contenttype, arguments=attributes)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sebastianw/dev/moin/src/moin/converters/markdown_in.py", line 632, in __call__
    self.convert_embedded_markup(converted)
  File "/home/sebastianw/dev/moin/src/moin/converters/markdown_in.py", line 540, in convert_embedded_markup
    self.convert_embedded_markup(child)
  File "/home/sebastianw/dev/moin/src/moin/converters/markdown_in.py", line 540, in convert_embedded_markup
    self.convert_embedded_markup(child)
  File "/home/sebastianw/dev/moin/src/moin/converters/markdown_in.py", line 540, in convert_embedded_markup
    self.convert_embedded_markup(child)
  File "/home/sebastianw/dev/moin/src/moin/converters/markdown_in.py", line 536, in convert_embedded_markup
    node[idx] = self.embedded_markup(child)  # child is immutable string, so must do node[idx]
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sebastianw/dev/moin/src/moin/converters/markdown_in.py", line 519, in embedded_markup
    p_text = html_in_converter(f"<p>{text}</p>")
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/sebastianw/dev/moin/src/moin/converters/html_in.py", line 156, in __call__
    html_tree = HTML(html_str)
                ^^^^^^^^^^^^^^
  File "/home/sebastianw/dev/moin-venv-python3/lib64/python3.11/site-packages/emeraldtree/html.py", line 191, in HTML
    parser.feed(text)
  File "/usr/lib64/python3.11/html/parser.py", line 110, in feed
    self.goahead(0)
  File "/usr/lib64/python3.11/html/parser.py", line 172, in goahead
    k = self.parse_endtag(i)
        ^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.11/html/parser.py", line 413, in parse_endtag
    self.handle_endtag(elem)
  File "/home/sebastianw/dev/moin-venv-python3/lib64/python3.11/site-packages/emeraldtree/html.py", line 128, in handle_endtag
    self.handle_endtag(lasttag)
  File "/home/sebastianw/dev/moin-venv-python3/lib64/python3.11/site-packages/emeraldtree/html.py", line 126, in handle_endtag
    lasttag = self.__stack.pop()
              ^^^^^^^^^^^^^^^^^^
IndexError: pop from empty list

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