Vue v-html & updated

HTML

<div id="app">
  <t-markdown :src="inp"></t-markdown>
  <button @click="change">change</button>
  updated: {{count}}
</div>

<script type="text/x-template" id="t-markdown">
   <div v-html="markup()"></div>
</script>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: sans-serif, Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
}

Vue

Vue.component('t-markdown', {
  template: '#t-markdown',
  props: {src:String},
  methods: {
    markup: function() { return this.src.slice(0,11) },
  },
  updated: function() { this.$parent.count++ },
});

new Vue({
  el: "#app",
  data: {count:0, inp:'<b>src</b> '},
  methods: {
    change: function() { this.inp += '#' },
  },
})