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.
Installation Finished Screen/10.1
The screen shown in Figure 3.5a appears once the installation is complete. It again provides the opportunity to save the installation configuration to a USB stick.
Click the "Finish" button to reboot into your PC-BSD® installation. Wait until the installer exits before removing the installation media.