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.
The "Remote login" tab, shown in Figure 8.6b, is used to configure, a protocol that comes with Xorg and allows a connection to an X session from a remote system. Uncheck the "Enable XDMCP" box to enable this service and expose the configuration options. By default, XDMCP uses UDP port 177, allows one connection per host, and allows up to 16 simultaneous sessions.
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