This toggle turns the display of include file text in the
active window on and off. A bullet appears next to the
command name on the menu when the toggle is on.
 
Use this command only if your program contains a $INCLUDE
metacommand.
 
When Included Lines is on, the include file text appears in
low-intensity video following the $INCLUDE metacommand that
names it. These displayed lines are read-only. You must load
the include file into a dedicated View window to edit them.