Line break in HTML with '\n'

You can use CSS white-space property for \n. You can also preserve the tabs as in \t.

For line break \n:

white-space: pre-line;

For line break \n and tabs \t:

white-space: pre-wrap;

document.getElementById('just-line-break').innerHTML = 'Testing 1\nTesting 2\n\tNo tab';

document.getElementById('line-break-and-tab').innerHTML = 'Testing 1\nTesting 2\n\tWith tab';

#just-line-break {
  white-space: pre-line;
}

#line-break-and-tab {
  white-space: pre-wrap;
}

<div id="just-line-break"></div>

<br/>

<div id="line-break-and-tab"></div>

This is to show new line and return carriage in HTML, then you don't need to do it explicitly. You can do it in CSS by setting the white-space attribute pre-line value.

<span style="white-space: pre-line">@Model.CommentText</span>