Nur die Anzeige der Ordner/Lesezeichenanzahl in einer anderen Farbe darstellen

(function() {

    if (!window.gBrowser)
        return;

    function setFunction() {

        const css =`
            .countClass::after {
                content: attr(data-value); 
                color: red;
            }
        `;

        const sss = Cc['@mozilla.org/content/style-sheet-service;1'].getService(Ci.nsIStyleSheetService);
        const uri = Services.io.newURI('data:text/css,' + encodeURIComponent(css));
        sss.loadAndRegisterSheet(uri, sss.AGENT_SHEET);

        let persToolBar = document.getElementById('PersonalToolbar');
        
        persToolBar.addEventListener('popupshowing', function onPopupShowing(aEvent) {
            let popup = aEvent.originalTarget;

            for (let item of popup.children) {
                if (item.localName != 'menu' || item.id?.startsWith('history'))
                    continue;
                setTimeout(() => {
                  let itemPopup = item.menupopup;
                  itemPopup.openPopup();
                  itemPopup.hidePopup();
                  let menuitemCount = 0;
                  let menuCount = 0;
                  for (let subitem of itemPopup.children) {
                    if (subitem.classList.contains('bookmark-item') && !subitem.disabled && !subitem.hidden) {
                      if (subitem.localName == 'menuitem') {
                        menuitemCount++;
                      } else if (subitem.localName == 'menu') {
                        menuCount++;
                      }
                    }
                  }
                  
                  let position = document.getElementsByClassName('label.menu-iconic-text')[0];

                  
                  let label = item.childNodes[1]; //label.menu-iconic-text
      
                  label.classList.add('countClass');
                  let strCountOut = "  (" + menuCount + "/" + menuitemCount + ")"
                  label.setAttribute('data-value', strCountOut);

                }, 100);
            }
        });
    }

    setTimeout(function() {
        setFunction();
    },50);
  
})();

(function() {

  if (!window.gBrowser)
    return;

  function setFunction() {
    PlacesViewBase.prototype._onPopupShowing = function PVB__onPopupShowing(aEvent) {

      let popup = aEvent.originalTarget;
      this._ensureMarkers(popup);
      if ("_delayedRemovals" in popup) {
        while (popup._delayedRemovals.length) {
          popup.removeChild(popup._delayedRemovals.shift());
        }
      }
      if (popup._placesNode && PlacesUIUtils.getViewForNode(popup) == this) {
        if (!popup._placesNode.containerOpen) {
          popup._placesNode.containerOpen = true;
        }
        if (!popup._built) {
          this._rebuildPopup(popup);
        }
        this._mayAddCommandsItems(popup);
      }

      /* original function end */

      for (let item of popup.children) {
        if (item.localName != 'menu' || item.id?.startsWith('history'))
          continue;
        setTimeout(() => {
          let itemPopup = item.menupopup;
          itemPopup.openPopup();
          itemPopup.hidePopup();
          let menuitemCount = 0;
          let menuCount = 0;
          for (let subitem of itemPopup.children) {
            if (subitem.classList.contains('bookmark-item') && !subitem.disabled && !subitem.hidden) {
              if (subitem.localName == 'menuitem') {
                menuitemCount++;
              } else if (subitem.localName == 'menu') {
                menuCount++;
              }
            }
          }
          if (!item.labelOriginal) {
            item.labelOriginal = item.label;
          }
          item.labelSuffix = '  (' + menuCount + '/' + menuitemCount + ')';
          item.label = item.labelOriginal + item.labelSuffix;
        }, 100);
      }

      popup.addEventListener('popuphidden', function onPopuphidden(event) {
        if (event.target != this)
          return;
        popup.removeEventListener('popuphidden', onPopuphidden);
        for (let item of popup.children) {
          if (item.localName == 'menu') {
            if (item.labelOriginal) {
              item.label = item.labelOriginal;
              item.labelOriginal = undefined;
            }
          }
        }
      });

    }

  }

  setTimeout(function() {
      setFunction();
  },50);
  
})();