Confusing bit of text in Ch3

[bugadani]

https://github.com/richardanaya/tour_of_rust/blob/84568bf70bba4b2702eb509867d828def86295c9/lessons/en/chapter_3.yaml#L86

I might be wrong here, but I think a String struct is stack-allocated, so the reference to the actual heap-allocated memory is itself stack allocated.