Sorry for the inconvenience.  Known Navigation header breakage, its being "rebuilt."
There may be other unforeseen breakage primarily in the handbook portion of the wiki.
The Table Of Contents section of each "PC-BSD® Users Handbook" page may be the best workaround.

Pages that link to "Category:System Manager"

Jump to: navigation, search
What links here    
Filters Hide transclusions | Hide links | Show redirects

No pages link to Category:System Manager.

Personal tools
Namespaces

Variants
Actions
Navigation
Toolbox