file-name-shadow-tty-properties

file-name-shadow-tty-properties is a variable defined in `rfn-eshadow.el'.
Its value is

(before-string "{" after-string "} " field shadow)

Documentation:
Properties given to the `shadowed' part of a filename in the minibuffer.
Only used when `file-name-shadow-mode' is active and Emacs
is not running under a window-system; if Emacs is running under a window
system, `file-name-shadow-properties' is used instead.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 22.1 of Emacs.