The API design could be better. Document fragments are designed to be reused.
It should accept an optional fragment key which accepts a document fragment.If not a fragment, throw, if has children, empty contents first.
replies(1):
They empty their contents into the new parent when they're appended, so they can't be meaningfully appended a second time without rebuilding them.
`<template>` is mean to be reused, since you're meant to clone it in order to use it, and then you can clone it again.
https://ibrahimtanyalcin.github.io/Cahir/
the whole rendering uses a single fragment.
https://dom.spec.whatwg.org/#mutation-algorithms
> To insert a node into a parent before a child [...]:
> If node is a DocumentFragment node:
> Remove its children