I had a string and I found out it had double line breaks, something like this:

A phrase...

Another phrase...

Another phrase...

But I wanted it to have online 1 line break in it instead:

A phrase...

Another phrase...

Another phrase...

Here’s what I did to get the result I wanted:

text = text.replace(/[\r\n]{2,}/g, '\n\n')

If regular expressions are a mystery to you, check my regular expressions guide.