[Vuejs]-Failed to mount component: template or render function not defined in Vuejs

Yes, finally found the issue. Inside the app.js file I previously defined the component as follows:

Vue.component('component', require('./components/component.vue')); 

but after upgrading webpack and related dependencies to v4, we need to require it with .default property.

Vue.component('component', require('./components/component.vue').default);