show-paren-when-point-in-periphery

show-paren-when-point-in-periphery is a variable defined in `paren.el'.
Its value is

nil

Documentation:
If non-nil, show parens when point is in the line's periphery.
The periphery is at the beginning or end of a line or in any
whitespace there.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 25.1 of Emacs.