What is Noreferrer and Nofollow?
What is a Nofollow Link?
What is a Noreferrer Link?
The difference is that, in theory, rel=”noreferrer” should not have any SEO impact, while nofollow clearly specifies that the link does not endorse in any way the target URL.
nofollow was invented by Google back in 2005 in order to fight comment spam in blogs, any URL appearing in the comment section would not pass PR to the target webpage.
rel=”noreferrer” mainly affects analytics, how did this visit landed to this page? where comes it from? noreferrer specifies to hide that kind of information.
I said in theory because there is currently no official documentation that explicitly indicates using noreferral would change anything in SEO terms, but it shouldn’t.
On top of this, target=”_blank” is also a security vulnerability. The new page has access to your window object via window.opener, and it can navigate your page to a different URL using window.opener.location = newURL.