Uncaught ReferenceError: Vue is not defined but sill works code example
Example: Vue is not defined
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/1.0.18/vue.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/1.0.18/vue.min.js"></script>