Vue.js

# Transition Group Root Element
кардинальное изменение

# Overview

<transition-group> no longer renders a root element by default, but can still create one with the tag attribute.

# 2.x Syntax

In Vue 2, <transition-group>, like other custom components, needed a root element, which by default was a <span> but was customizable via the tag attribute.

<transition-group tag="ul">
  <li v-for="item in items" :key="item">
    {{ item }}
  </li>
</transition-group>
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# 3.x Syntax

In Vue 3, we have fragment support, so components no longer need a root node. Consequently, <transition-group> no longer renders one by default.

  • If you already have the tag attribute defined in your Vue 2 code, like in the example above, everything will work as before
  • If you didn't have one defined and your styling or other behaviors relied on the presence of the <span> root element to work properly, simply add tag="span" to the <transition-group>:
<transition-group tag="span">
  <!-- -->
</transition-group>
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# Migration Strategy

Migration build flag: TRANSITION_GROUP_ROOT

# See also