Issue with "once" event modifier

[amrdoe]

Version

2.5.17

Reproduction link

https://codepen.io/AmrIKhudair/pen/YRLEYo

Steps to reproduce

1- open the minimal reproduction
2- Type something (notice that the first time you focus the last input a new input appears)
3- delete one of the todos (other than the last one)
4- Focus the last one again (now a new todo is not created)

What is expected?

A new todo is created

What is actually happening?

A new todo isn't created

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I think it has something to do with reusing dom elements for improving performance

[posva]

Duplicate of #8032