I think they are referring to literal text/whitespace in the template. I don't know about other implementations, but typescript mutates the whitespace if newlin

I think they are referring to literal text/whitespace in the template. I don't know about other implementations, but typescript mutates the whitespace if newlines are involved. It seems that the rules are, for any run of literal text: - preserve runs of whitespace that don't contain newlines - drop initial and final whitespace if it contains a newline - collapse any internal runs of whitespace containing newlines to a single space. (based on a quick experiment with tsc.)