I actually had to change it in 4 places... In entity/comment_add.php too. What version of php are you using? I'm using php 7.2 now. It works on your site, should work on mine too.

Here is how it sopose to look:

$text = $('#comment-box-<?php echo $object; ?>').html();
                $text = $replace_tags($text, '<div>').replace(/\<div\\?>/g, "<br>");
                $text = $replace_tags($text, '<br>').replace(/\<\/div\\?>/g, "<br>");
                $text = $replace_tags($text, '<br>').replace(/\<br\\?>/g, "\n");

YOU and only you, have to edit it 3 times, and set to "True" in JS 2 times.

I honestly don't know how to help you at this point. Everything had been chewed up. I can only guess you didn't edit something right.

Ok, how on earth did you get all that? Anywho, glad you could get it to work. Why is it not working on my site?

Just because i'm bored and wanted to see what is up. I grabbed your submit button with a extra JS you had in comments_add. Everything works.

I did! In order to keep from causing a submit on enter I had to change the 2 false statements to true. In order to get the non-breaking page space between the lines I had to use ~Z~ Man's addition. Now, what do I need to get a breaking space or a div between the two lines?

Now we probably just confusing other people.

change the 2 false statements

Did you add 2 extra lines Z-man provided to those 2 statements as well?

Pardon... it now gives one non-breaking page space on submit.

Ok, so I checked that file and sure enough, there was a secondary JavaScript I had to edit. Now it gives one breaking space but no <br> or \n after the enter. Secondly, you still have to change the 2 false statements to true to keep it from posting when you hit enter.

Allon Prooit
As Z-man said:

I have no idea about your 'upgraded' OssnComments component...

As I looked at your code, you have implimented submit button, so the code you have to edit is not in JS folder, it is in:
OssnComments/plugins/default/forms/OssnComments/post/comment_add.php

When paying someone for addons, check what they add.