[Vuejs]-Vue plugin (learning) After publish or local test causes Failed to mount component: template or render function not defined

You can import and register VueAutocompletion locally in your Vue component.

import VueAutocompletion from 'vue-autocompletion'
export default {
   components: {
      VueAutocompletion 
   },
   data () {
   ...

In your codes, the registered component name vue-autocompletion and used name in template vue-auto-completion are different from each other.

They should be the same.

<vue-auto-completion
...
components: {
  'vue-auto-completion':VueAutocompletion
},