How to import Vue components from browser - via CDN
The example you posted works fine, here is a working example.
new Vue({ el: "#app", data: { msg: "Vue js Hello World - Your First Vue.js App" }});<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script><script src="https://unpkg.com/@chenfengyuan/vue-qrcode@1.0.1/dist/vue-qrcode.min.js"></script><script>Vue.component(VueQrcode.name, VueQrcode);</script><div id="app"> <h1>{{ msg }}</h1> <qrcode value="https://queue-r.glitch.me" :options="{ width: 200 }"></qrcode></div>