Variable: display-fill-column-indicator-column
display-fill-column-indicator-column is a customizable and
buffer-local variable defined in C source code.
Documentation
Column for indicator when display-fill-column-indicator is non-nil.
The default value is t which means that the indicator
will use the fill-column variable. If it is set to an integer the
indicator will be drawn in that column.
See Info node (emacs)Displaying Boundaries for details.
This variable was added, or its default value changed, in Emacs 27.1.
Source Code
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