I used following command in a repeating commandblock:

/tellraw @p ["",{"text":"this\nis\na\ntext\nwhich\nshould\nbe\ndisplayed\non\nmultiple\nlines\nwithout\nany\nerrors"}]

Then I opened the chat and scrolled up and down.

What I expected to happen was...:
Just to see this text everywhere like you used to.

What actually happened was...:
The hight of the chat changes

Steps to Reproduce and demonstration:
Youtube Video