Java PX Recognize \r\n to <br> but it didn't work

When I coding like this. It did not line feed to next row, and it show <br> like the picture.

But when I do the same thing on event px and it work.

Is there any solution to solve the problem?

version: 9.3.5

PX return:

return new ActionResult(ActionResult.STRING, "Hello world");

Event return:

return new EventActionResult(req, new ActionResult(ActionResult.EXCEPTION, new Exception("Hello \r world")));