I came across the refresh_initrd script while searching for packages that still
use mkinitrd in Tumbleweed, because it's deprecated and will be removed in the
near future (see bug #1202351).

But, this script it's not even working with the current mkinitrd version, which
is just a wrapper that internally calls dracut and update-bootloader. If
"$SPLASH = yes", it's called with the "-s auto" arguments, which are not
implemented, producing "mkinitrd: boot splash not yet supported" (see
https://github.com/openSUSE/dracut/blob/adedcbc79f4a467380147e5bba2e4f2402252c51/suse/mkinitrd-suse.sh#L281-L283).

Also, it doesn't detect a change of a kernel module if it's compressed. The
code should be:

-    module=${module%.ko}
+    module=${module%.ko*}

So, I don't know the plans or current usage of this script, but it would
require some tweaking, or just removing it if it's no longer used.