anchor.diff:  begin
     if fDoc <> aDoc then exit;
     fDoc := nil;
  +  clearTree;
  +  updateVisibleCat;
     beginUpdateByDelay;
   end;
   
  
positive.code:     procedure actRefreshOnFocusExecute(Sender: TObject);
      procedure actCopyIdentExecute(Sender: TObject);
      procedure updateVisibleCat;
      //
      procedure produceJsonInfo;
      procedure jsonInfoProduced(sender: TObject);
  
negative.code: begin
    if ndAlias = nil then exit;
  
    clearTree;
    updateVisibleCat;
  
    if not FileExists(fJsonFname) then exit;
  