viper-use-replace-region-delimiters

viper-use-replace-region-delimiters is a variable defined in `viper-init.el'.
Its value is

t

Documentation:
If non-nil, Viper will always use `viper-replace-region-end-delimiter' and
`viper-replace-region-start-delimiter' to delimit replacement regions, even on
color displays. By default, the delimiters are used only on TTYs.

You can customize this variable.