FIX: Make sure rel attributes are correctly set. (PR #10645)

We must guarantee that “rel=noopener” was set if “target=_blank” is present, which is not always the case for trusted users. Also, if the link contains the “nofollow” attribute, it has to have the “ugc” attribute as well.


Looks great! Also looks like we have quite a few of brittle tests but hopefully they don’t change too often.