Sorry for the inconvenience.  Known Navigation header breakage, its being "rebuilt" but forward nav should be ok now.
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.

Translations:Booting Into PC-BSD®/9.2/33/en

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The settings in this screen are described in more detail in Display. If you wish to return to this display wizard at a later time, go to Control Panel → Display.

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