For some reasons I have to use Typo3 besides my beloved Drupal and I faced the problem that I want to add the rel="nofollow" attribute to all external links.

I googled a lot to solve this and since I’m no TypoScript expert, honestly I’m not even a rookie, I had to find a different solution. I found one that is for different CSS styles, but it’s a bit of a dirty hack.

1
styles.content.links.extTarget = _self" rel="nofollow

I tried that out and it works fine for me.