Problem:
With this function I can only set the first and last line of the tablist for the "testuser" player

but I want to set more lines for the header, as you can do here:

Using the same syntax the tablist doesn't work. I tried a few tries but I couldn't figure out how to go to a new line and start a new line. Is there a way to do this or is it a feature that hasn't been added?

Plugin version: The latest (5.4.8).

Software: Paper
Version: 1.15.2

Relevant plugins:
EssentialsX
Placeholder API
LuckyPerms

Insert the list here to see how you used.

I made other attempts and I realized that to go to the end you have to write \n, Thanks all the same for your time!