# RETRO 2020.4 - remove deprecated words as{ }as " prefix:" - examplse markdown.retro - future Prior RETRO images had a patch that allowed underscores to be used in word names. In this release, the patch is no longer part of the standard library, but is still included on Unix targets by default. This might affect some users, if you are building a custom image, load package/allow-underscores-in-names.forth if you need this.