Teleport cannot be used multiple times

[ghost]

Version

3.0.0-rc.6

Reproduction link

https://codepen.io/team/Vue/pen/gOPNvjR

Steps to reproduce

1. Click "Open full screen modal! (With teleport!)"
2. Click "Close"

What is expected?

The modal should close.

What is actually happening?

Clicking close on the modal provides an error "Uncaught (in promise) TypeError: Cannot read property 'insertBefore' of null".

I'm pretty sure this is a duplicate of #1903, but I'm honestly not 100%, so I figured I'd submit this issue just in case.

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I first noticed this in one of my own projects. Then, when looking at the teleport documentation (https://v3.vuejs.org/guide/teleport.html), I ran the codepen provided and got the same error. The codepen that I linked is the code that's supposed to demo the teleport.

The error is prefaced with the warning: "This is likely a Vue internals bug. Please open an issue.."

[yyx990803]

Yeah, it's fixed by the same commit (tested from latest master)