code: def show_current_metadata(self):
          
          LOGGER.debug('Showing layer: ' + self.layer.name())
          keywords = KeywordIO(self.layer)
          content_html = keywords.to_message().to_html()
          full_html = html_header() + content_html + html_footer()
          self.metadata_preview_web_view.setHtml(full_html)
docs: Show metadata of the current selected layer.