Basic VueJs Component with flatpickr directive (broken)

POC of a flatpickr directive - broken on mobile working: https://jsfiddle.net/escapedcat/xyvuq2jv/

HTML

<link rel="stylesheet" href="https://cdn.rawgit.com/chmln/flatpickr/v3.0.5-1/dist/flatpickr.css">
<script src="https://cdn.rawgit.com/chmln/flatpickr/v3.0.5-1/dist/flatpickr.js"></script>
<script src="https://rawgit.com/vuejs/vue/v2.3.4/dist/vue.js"></script>
<div id="app">
  <greeting v-model="tmp"></greeting>
  {{ tmp }}
</div>

JavaScript

Vue.component('greeting', {
  template: '<div><h1>Welcome to flatpickr!</h1><input type="text" v-flatpickr="{}" /></div>'
});

Vue.directive('flatpickr', {
  bind: (el, binding) => {

console.log('flatpickr bind', el)

    el._flatpickr = new flatpickr(el, binding.value)

  },
  unbind: el => el._flatpickr.destroy()
})


// create a new Vue instance and mount it to our div element above with the id of app
var vm = new Vue({
  el: '#app',
  data: {
  	tmp: null
  }
});