`TypeError: Cannot set property 'nodeValue' of null` happens when trying to sort table rows having a slot

[yamacent]

Version

3.0.0-beta.3

Reproduction link

https://jsfiddle.net/2kqhnj1y/1/

Steps to reproduce

click table header ( th ) and then you will have the error on the console.

What is expected?

the error does not happen and rows are sorted correctly

What is actually happening?

the error happens and sort function is not triggered

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If I delete a slot inside my-table, it works correctly