Very old versions of this package used ucf to mediate changes to /etc/fonts/local.conf, but since etch (2007), the only use of ucf has been to remove all record of /etc/fonts/local.conf when purged. That use of ucf is guarded by a check for the existence of the executable, and the dependency has no practical effect there, because purging a package from "config files remain" state does not guarantee to have non-Essential dependencies satisfied.
In Steam Runtime containers based on Debian >= 10, this change was sufficient to allow ucf to be dropped altogether, reducing the size of the container image.
Closes: #915114