What is the regular expression to remove all similar strings?

Question

PHP

There is a module for parsing SimplePars, it works on Opencart and uses regular expressions for search and replace. In the instructions for it ( https://simplepars.top/index.php?page=note&n=37 ) I found the rule

{reg[#^(.*?)\s+?^(?=.*^\1$)#m]}| - Will delete two identical rows one after the other

How to write a rule that will remove all identical lines, not just consecutive ones?

Answer 1

Answer to my question
{reg[#^(.*?)\R+(?=(?s:.*?)^\1$)#m]}|