I am using String.fromCharCode to add new line (or) carriage return to my html text.
String.fromCharCode
It is like,
\"Ant the other line here...\" + String.fro
If you want a line break in HTML you need to supply entity instead of a line break (your String.fromCharCode(13) code) since HTML interprets line breaks as usual spaces in text.
String.fromCharCode(13)