There are two conditions.
'input' is used.
The new one is attached before the other ones.
Code and Environment
How to Do
Write what you want in 'id: 1 | index: 1' of both parts.
Click the 'add' button.
|'key' is 'index'|
What you wrote before follows 'index'. So, it is in 'id: 2 | index: 1'
|'key' is 'id'|
What you wrote before follows 'id'. So, it is in 'id: 1 | index: 2'