JSFiddle - React, Tailwind, and code Playground

HTML

<div data-bind="event:{keydown:testMethod}">
    <label>A-Label</label>
    <textarea></textarea>
    <button>A Button</button>
</div>
<div>Some text outside the area</div>
<label>Presses:</label><span data-bind="text:pressCount"></span>

JavaScript

var vm = {
    pressCount: ko.observable(0),
    testMethod: function (element, eventArgs) {
        vm.pressCount(vm.pressCount() + 1);
        var prevent = eventArgs.keyCode === 13;
        return !prevent;
    }
};

ko.applyBindings(vm);