Option 1 - Use a pre tag:
It's actually best (or efficient) that you wrap text in a <pre></pre>
tag, which will preserve the white space in the text.
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/pre
And enable word-wrap
How do I wrap text in a pre tag? - http://jsfiddle.net/X5ZY7/
Option 2 - Split your string into lines, and use a mustache each:
comment = userComment.split("\n")
{{#comment}}
{{comment}}<br/>
{{/comment}}
Option 3 - Manually escape your string using your favorite method before injecting the
tags:
var div = document.createElement("div")
div.textContent = comment
comment = div.innerHTML.replace(/\n/g, "<br/>")
{{{comment}}}