Box drawings light horizontal
On Windows, hold Alt and type 196 on the number pad, then let go of Alt.
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About the box drawings light horizontal
The original IBM PC’s character set, now known as code page 437, included lines, corners and junctions for drawing boxes on a text-only screen. DOS programs used them to build windows, menus and tables. Unicode keeps them in its Box Drawing block of 128 characters, and they still appear in command-line tools and in comments in source code.