JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://github.com/downloads/SteveSanderson/knockout/knockout-2.1.0.js"></script>
<div contentEditable="true" data-bind="editableText: div"></div>

<button data-bind="click: showObservablesContent">Show observable's content</button>

CoffeeScript

ko.bindingHandlers.editableText =
  init: (element, valueAccessor) ->
    $(element).on 'blur', ->
      observable = valueAccessor()
      observable $(@).text()
  
  update: (element, valueAccessor) ->
    value = ko.utils.unwrapObservable valueAccessor()
    $(element).text value

    
class ViewModel
  constructor: ->
    @div = ko.observable('foobar');
  
  showObservablesContent: =>
    alert @div()

ko.applyBindings new ViewModel()