anchor.diff:  
           // when reclicking a filename then scroll to next diff-chunk.
           // But not when returning to a previously scrolled file.
  -        if (sectionCount > 0 && (reClicked(filename) || !alreadyOpened.includes(filename))) {
  +        if (diff.section_count > 0 && (reClicked(filename) || !alreadyOpened.includes(filename))) {
             const $diffSheet = $(`[id="diff_file_content_for_${filename}"]`);
             const section = $(`#${diff.id}_section_${sectionIndex}`);
             const halfSecond = 500;
  
positive.code:             scrollTop: '+=' + (section.offset().top - 250) + 'px'
            }, halfSecond);
            sectionIndex += 1;
            sectionIndex %= sectionCount;
          }
          param.filename = filename;
          alreadyOpened.push(filename);
  
negative.code: 
    // - - - - - - - - - - - - - - - - - - - - - - - -
    const buildDiffFilenameHandlers = (diffs) => {
      // Builds filename click handlersfor a [ kata-id, was-index, now-index] tuple.
      const reClicked = (filename) => param.filename === filename;
      const alreadyOpened = [];
  
      const loadFrom = (diff) => {
        const filename = diffFilename(diff);
        let sectionIndex = 0;
        return () => {
          // select line-counts
          $('.diff-line-count').attr('disabled', true);
  