DOM Parts / Template Parts: conflicting name with CSS parts

[dy]

There's part attribute / CSS pseudo for custom elements:

<template id="tabbed-custom-element">
<div part="tab active">{{ tab[0] }}</div>
<div part="tab">{{ tab[1] }}</div>
<div part="tab">{{ tab[2] }}</div>
</template>

<tabbed-custom-element></tabbed-custom-element>

<style>
tabbed-custom-element::part(tab) {
  color: #0c0dcc;
  border-bottom: transparent solid 2px;
}

tabbed-custom-element::part(active) {
  background-color: #0c0d19;
}
</style>

If we wanted to have access to all element parts, that could be implemented as el.part.tab.
Same time, it would conflict by meaning with DOM/Template parts, had the proposal been promoted - here parts have meaning fields: el.parts.tab[0] = 'Tab1'

[dy]

Duplicate #902