Sorry for the inconvenience. Known Navigation header breakage.
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.
Create your own spin of PC-BSD®
This seems to be a Linux concept, but people have been requesting instructions on how it may be done. Until greater detail can be added here, the two links below may be what is necessary. Those who seek to make a spin may have a better idea about this and can assist in fleshing out this page. The key word spin will also redirect here.