ps-fg-validate-p

ps-fg-validate-p is a variable defined in `ps-print.el'.
Its value is

t

Documentation:
Non-nil means validate if foreground color is different than background.

If text foreground and background colors are equals, no text will appear.

See also `ps-fg-list'.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 22 of Emacs.