anchor.diff:              .header_navigation
   
                 .navi_point.title(class=("current_page" if not mode or mode=="sorted" else ""))
  -                a(href=url_for("questions", tag=tag))= _("sorted")
  +                a(href=url_for("questions", tag=tag|default(None)))= _("sorted")
   
                 .navi_point.top(class=("current_page" if mode=="top" else ""))
  -                a(href=url_for("questions", mode="top", tag=tag))= _("top")
  +                a(href=url_for("questions", mode="top", tag=tag|default(None)))= _("top")
   
                 .navi_point.overview(class=("current_page" if mode=="custom" else ""))
                   a(href=url_for("questions", mode="custom"))= Antragsgruppen
  
positive.code: 
                .header_title
                  a(href="/") Arguments
                
                if current_user.is_authenticated()
                  .header_menu
                    .username= current_user.display_name
                      .up_arrow
  
negative.code:         a(href="/")
            .footer_logo
          #footer_copyright
            a(href="#") FAQ
            ||
            a(href="#")= _("terms_of_use")
            ||
            a(href="#")= _("link_other")
            ||
            a(href="#")= _("imprint")
  
  
  