Attributes
nofollow
Tell Web Scrapers not to index the URL specified specified in the link
noopener
Navigate to the target resource without granting access to the document that opened it.
Cases
noopenernot specified -Window.openerbrowser property passed to the new Web Page (hypertext document)rel=noopenerspecified -Window.openernot passed to the new Web Page and new browsing context cannot access any information about the previous page in JavaScript