Change Line-Breaks in Paragraphs by GREP/regex

Here is my Problem:
A Text set in CS6 uses a different character for Line-Breaks as CC.
Now there is the idea to run a script in CC2019 to convert Forced-Line-Breaks in Paragraphs via GREP/regex.

This code works, but not for those Line-Breaks. I didn't figure out the character.

// regex_changeContentsOfWordOrString_RemainFormatting.jsx   
// regards pixxxel schubser    
/* var s = /(\r\n|\r|\n)/; */  
/* var s = /\u000D/; */  
/* var s = /\u000C/; */  
/* var s = /^n/; */  
var s = /\n/; 
/* var s = /\u000A/; */ 
/* var s = /\u000D/; */ 
/* var replacer = "hello", result; */ 
/* var replacer = "bla", result; */   
/* var replacer = "\r", result; */ 
var replacer = /\r/, result;  
var atf = activeDocument.textFrames[0];      
while (result = s.exec(atf.contents)) {
       try {
           aCon = atf.characters[result.index];
           aCon.length = result[0].length;
           aCon.contents = replacer;
           } catch (e) {};
       }

Which character is it?

And here is the download-link for the test-file:
BlocksatzCS6.ai

Changed Line-Endings