In VueJS 2.x, every component must have a single root element when template has more than one element. In this case, you need to wrap the elements with a parent element.
<template>
<div class="todo-item">
<h2>{{ title }}</h2>
<div v-html="content"></div>
</div>
</template>
Otherwise there will an error throwing, saying that "Component template should contain exactly one root element...".
Whereas in 3.x, components now can have multiple root nodes. This way of adding multiple root nodes is called as fragments.
<template>
<h2>{{ title }}</h2>
<div v-html="content"></div>
</template>
