View Right Margin Rule
Menu: View > Right Margin Rule
Default Shortcut Key: Alt+F6
Macro function: ViewRightMarginRule()
The View Right Margin Rule command is used to toggle on and off the display of a thin vertical line which marks a user-defined column. The Right Margin Rule can be used as a visual reminder that a particular line length has been exceeded.
You can set the Right Margin Rule to any column you desire; the default is column 80. An option is provided to set the column on the Configure | Preferences | Display options page. The option is titled Show right margin rule at column...
Clicking on the Right Margin Rule with the right mouse button provides access to its context menu, which allows the line to be turned off.