When using Quasar UMD mode, I found an error that appeared in IE but not FF nor Chrome. Here is the console error msg:

And my demo code:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<link
href="https://fonts.googleapis.com/css?family=Roboto:100,300,400,500,700,900|Material+Icons|Material+Icons+Outlined"
rel="stylesheet" type="text/css">
<link href="https://cdn.jsdelivr.net/npm/@mdi/font@^4.0.0/css/materialdesignicons.min.css" rel="stylesheet"
type="text/css">
<link href="https://cdn.jsdelivr.net/npm/animate.css@^3.5.2/animate.min.css" rel="stylesheet" type="text/css">
<link href="https://cdn.jsdelivr.net/npm/quasar@1.9.9/dist/quasar.min.css" rel="stylesheet" type="text/css">
</head>
<body>
<div id="q-app">
<q-item dense>
<q-item-section>
<q-item-label>Time zone</q-item-label>
</q-item-section>
<q-item-section>
<q-select dense outlined options-dense :options='timezoneOptions' v-model='timezone' emit-value
map-options></q-select>
</q-item-section>
</q-item>
</div>
<script src="https://cdn.jsdelivr.net/npm/quasar@1.9.9/dist/quasar.ie.polyfills.umd.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/vue@^2.0.0/dist/vue.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/quasar@1.9.9/dist/quasar.umd.min.js"></script>
<script>
new Vue({
el: '#q-app',
data: function () {
return {
timezone: 1,
timezoneOptions: [
{ label: '(GMT-12:00) Eniwetok, Kwajalein', value: 0 },
{ label: '(GMT-11:00) Midway Island, Samoa', value: 1 }
// ... the rest of timezone
]
}
}
})
</script>
</body>
</html>
Thanks for helping me!