code: function getFirstFont(fonts, skipSystemFonts) {
    let regularFont = undefined;
    let systemFont = undefined;
  
    fonts.split(',').forEach(font => {
      font = font.trim().replace(/^["']+|["']+$/g, '');
      if (font === '') {
        return;
      }
  
      // See above for a note on OS-specific fonts
      if (!regularFont && (!skipSystemFonts || SYSTEM_FONTS.indexOf(font) < 0)) {
        regularFont = font;
      }
      if (!systemFont) {
        systemFont = font;
      }
    });
  
    if (regularFont) {
      return regularFont;
    }
  
    if (systemFont) {
      return systemFont;
    }
  
    return '-apple-system';
  }
docs: INPUT: -apple-system, "Helvetica Neue", Helvetica, Arial, sans-serif OUTPUT: Helvetica Neue