Vue.js vue中的嵌套转换组不工作 过渡组中的过渡组不工作。

截面树组件：

Transition group inside transition group is not working.

 <transition-group name="slide">
      <section-tree v-for="(section,index) in form.sections" :key="section.random"
            :index = "index"
            :section = "section"
            :sections="form.sections"
            @removeSection="removeSection"
            @selectedSectionAndLesson="selectedSectionAndLesson"
      >
      </section-tree>
 </transition-group>

 <transition-group name="slide">
    <lesson-tree v-for="(lesson,ind) in section.lessons" :key="lesson.random"
         :section-index="index"
         :index="ind" :lesson="lesson" :section="section" :sections="sections"
         @selectedLesson="selectedLesson"
         @removeLesson="removeLesson"
    >
    </lesson-tree>
</transition-group>