vue 2.3.x, v-if do not append element before element moved away

[harvey-woo]

<template>
    <div>
        <a @click="showElement = true">Show Element</a>
        <div v-if="showElement" class=“element”>element</div>
        <div v-dom-portal></div>
    </div>
</template>
<script>
    export default {
        data: () => ({ showElement: false })
    }
</script>

v-if do not append element before element which had been moved away,
Tested in vue 2.2.6 represent correct, but not in vue 2.3.0, even 2.3.2

[luozhihua]

same problem.

[zhangjingrm]

same problem

[martSforever]

same problem