Chris Deeming
1) It isn't recommended to change the core XenForo files as changes you make will be lost whenever there is a new release.
2) Also, the functionality mentioned is DEFAULT within XenForo. All URLs posted on the forum by anyone other than a staff member is automatically given the rel="nofollow" attribute.
3) The only part of value is the exception list but I refer you back to 1).
From: http://xenforo.com/community/resources/how-to-add-rel-nofollow-to-link.729/
Needs to be checked after live import
Chris Deeming 1) It isn't recommended to change the core XenForo files as changes you make will be lost whenever there is a new release.
2) Also, the functionality mentioned is DEFAULT within XenForo. All URLs posted on the forum by anyone other than a staff member is automatically given the rel="nofollow" attribute.
3) The only part of value is the exception list but I refer you back to 1).