How can I paste a multiple line text paragraph into a text variable?

I use feedback text in a variable and I can't figure out how to paste multiple-line text into the variable box. Nor how to make a Carriage Return inside the text box editor.

Only the first line is included; the rest is truncated. I can't press Enter because this closes the input. 

It worked fine in the beginning, but no more. And I have no idea how to make it accept pasted text.

I use Notepad to get unformatted text first, then paste it inside the box.