Check out example codes for "The template root requires exactly one element.eslint-plugin-vue". It will help you in understanding the concepts better.
Code Example 1
Change the code in App.vue from as follows:-
<template>
<section> // add this section tag here
<img alt="Vue logo" src="./assets/logo.png">
<HelloWorld msg="Welcome to Your Vue.js App" />
</section> // end section here
</template>
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