v2.1.0

Fixed

• Close tags more correctly, even if the end tag has trailing text.

  For example, </tag bonus> now closes <tag> correctly.
  The trailing content is not available to parsers.

• Fix quadratic CPU usage in SGMLParser.feed().

  This can occur when a large document with an unfinished token
  (like <a href="...) is fed into the parser in very small increments.

  The new implementation doesn't significantly change peak memory usage.

Changed

• Improve the closing tag search behavior of SGMLParser.finish_endtag().

  Previously, the method always searched the entire tag stack
  to close the innermost tag, which had a higher search cost.
  The tag stack is now searched in reverse order
  and breaks on the first matching tag.