Multiple Vuetify data-tables with expandable rows on same page - vuetify.js

Question

I'm using Vuetify's v-data-tables with expandable rows. The expandable rows work fine when there's only one v-data-table on the page. When I have multiple v-data-tables, the expandable rows no longer function. I'm assuming I'm missing something that would make each data table or slot unique?
CodePen: https://codepen.io/tapal/pen/poyOdBw (this is essentially the expandable rows CodePen from Vuetify's documentation but split into two tables).
new Vue({
el: '#app',
vuetify: new Vuetify(),
data() {
return {
expanded: [],
singleExpand: false,
headers: [{
text: 'Dessert (100g serving)',
align: 'start',
sortable: false,
value: 'name',
},
{
text: 'Calories',
value: 'calories'
},
{
text: 'Fat (g)',
value: 'fat'
},
{
text: 'Carbs (g)',
value: 'carbs'
},
{
text: 'Protein (g)',
value: 'protein'
},
{
text: 'Iron (%)',
value: 'iron'
},
{
text: '',
value: 'data-table-expand'
},
],
firstDessert: [{
name: 'Frozen Yogurt',
calories: 159,
fat: 6.0,
carbs: 24,
protein: 4.0,
iron: '1%',
},
{
name: 'Ice cream sandwich',
calories: 237,
fat: 9.0,
carbs: 37,
protein: 4.3,
iron: '1%',
},
{
name: 'Eclair',
calories: 262,
fat: 16.0,
carbs: 23,
protein: 6.0,
iron: '7%',
},
{
name: 'Cupcake',
calories: 305,
fat: 3.7,
carbs: 67,
protein: 4.3,
iron: '8%',
},
{
name: 'Gingerbread',
calories: 356,
fat: 16.0,
carbs: 49,
protein: 3.9,
iron: '16%',
},
],
secondDessert: [{
name: 'Jelly bean',
calories: 375,
fat: 0.0,
carbs: 94,
protein: 0.0,
iron: '0%',
},
{
name: 'Lollipop',
calories: 392,
fat: 0.2,
carbs: 98,
protein: 0,
iron: '2%',
},
{
name: 'Honeycomb',
calories: 408,
fat: 3.2,
carbs: 87,
protein: 6.5,
iron: '45%',
},
{
name: 'Donut',
calories: 452,
fat: 25.0,
carbs: 51,
protein: 4.9,
iron: '22%',
},
{
name: 'KitKat',
calories: 518,
fat: 26.0,
carbs: 65,
protein: 7,
iron: '6%',
},
],
}
},
})
<link href="https://cdn.jsdelivr.net/npm/vuetify#2.3.10/dist/vuetify.min.css" rel="stylesheet"/>
<script src="https://cdn.jsdelivr.net/npm/vue#2.x/dist/vue.js"></script>
<script src="https://cdn.jsdelivr.net/npm/vuetify#2.3.10/dist/vuetify.min.js"></script>
<div id="app">
<v-app id="inspire">
<v-data-table :headers="headers" :items="firstDessert" :single-expand="singleExpand" :expanded.sync="expanded" item-key="name" show-expand class="elevation-1">
<template v-slot:top>
<v-toolbar flat>
<v-toolbar-title>First Dessert</v-toolbar-title>
<v-spacer></v-spacer>
<v-switch v-model="singleExpand" label="Single expand" class="mt-2"></v-switch>
</v-toolbar>
</template>
<template v-slot:expanded-item="{ headers, item }">
<td :colspan="headers.length">More info about {{ item.name }}</td>
</template>
</v-data-table>
<hr />
<v-data-table :headers="headers" :items="secondDessert" :single-expand="singleExpand" :expanded.sync="expanded" item-key="name" show-expand class="elevation-1">
<template v-slot:top>
<v-toolbar flat>
<v-toolbar-title>Second Dessert</v-toolbar-title>
<v-spacer></v-spacer>
<v-switch v-model="singleExpand" label="Single expand" class="mt-2"></v-switch>
</v-toolbar>
</template>
<template v-slot:expanded-item="{ headers, item }">
<td :colspan="headers.length">More info about {{ item.name }}</td>
</template>
</v-data-table>
</v-app>
</div>