A JS 'class' for cloning complex HTML blocks - automatically adds numbers and nesting suffixes to new clones, properly increments values of ID and NAME attributes in new clones, adds deletion links if needed, allows nesting clones within clones, adds event listeners to cloning links and clone deletion links, allows skipping some nodes from pattern blocks and setting maximum clones number for a given target - a lot of parameters you can modify, optional use of user functions for a better control over a cloning process. Less than 10Kb in size, useful especially with complex forms.