# File lib/asciidoctor/document.rb, line 447
  def save_attributes
    unless @attributes.has_key?('doctitle') || (val = doctitle).nil?
      @attributes['doctitle'] = val
    end

    # css-signature cannot be updated after header attributes are processed
    if @id.nil? && @attributes.has_key?('css-signature')
      @id = @attributes['css-signature']
    end

    if @attributes.has_key? 'toc2'
      @attributes['toc'] = ''
      @attributes['toc-class'] ||= 'toc2'
    end

    @original_attributes = @attributes.dup
  end