JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://raw.github.com/ericmbarnard/Knockout-Validation/master/Src/knockout.validation.js"></script>
<script src="https://raw.github.com/AndersMalmgren/Knockout.BindingConventions/master/src/Knockout.BindingConventions.js"></script>
<ul data-name="items">
    <li><input data-name="name"></li>
</ul>
    <button data-name="add">Add</button>

JavaScript

ViewModel = function() {
    
    this.items = ko.observableArray();
    this.items.subscribe(function() {
         this.errors = ko.validation.group(this);
         this.errors.showAllMessages();
    }, this);
    
    this.items([
        new ItemViewModel("John"), 
        new ItemViewModel("Jane")
    ]);       
};

ViewModel.prototype = {
    add: function() {
        this.items.push(new ItemViewModel());
    }
};
        
ItemViewModel = function(name) {
        this.name = ko.observable(name).extend({ required: true });
};

ko.validation.init({ grouping: { deep: true, observable: true } });
ko.applyBindings(new ViewModel());