JSFiddle - React, Tailwind, and code Playground

HTML

<div data-bind="foreach: array">
    <div data-bind="text: $data"></div>
</div>

JavaScript

var vm = {
    array : ko.observableArray(["foo","bar"])
};

ko.applyBindings(vm);

function Add() {
    vm.array.splice(1,0,"ra");
}

Add();