Can’t use parenthesis “(” inside label of “multi lines text”

Hello,

I was trying to set up “Additional Fields”.
Worked fine but once I tried to use “(” or “)” inside the label of the “multi lines text” element, it won’t save the result. Seems like it only occurs for the multi lines text” element. Escaping did not help as well.

Also: is there a way to set a max. char limit for inputs?

Any idea how to resolve that issue?

Thanks!