I package the current Masterwork Linux dist (it's the only current one, AFAIK, so it appears you're using my package).
I'm running a Gentoo system (yes, still rockin' the Gentoo), and I recompile the video drivers to use current library versions - my system doesn't have the old ones included in vanila DF.
My system has this setup:
/bin/ls -ld /usr/lib*
lrwxrwxrwx 1 root root 5 Mar 16 2016 /usr/lib -> lib64
drwxr-xr-x 63 root root 86016 Mar 20 21:56 /usr/lib32
drwxr-xr-x 182 root root 176128 Mar 20 21:59 /usr/lib64
drwxr-xr-x 24 root root 4096 Mar 20 21:59 /usr/libexec
(which is why the paths all say "/usr/lib/...")
I'm not doing anything wacky with libraries, just using the distro defaults. Here's my ncurses:
$ /bin/ls -l /usr/lib/libncurs*
-rwxr-xr-x 1 root root 530 May 30 2018 /usr/lib/libncurses.so
lrwxrwxrwx 1 root root 17 May 30 2018 /usr/lib/libncurses++.so -> libncurses++.so.6
-rwxr-xr-x 1 root root 296056 Jan 16 2018 /usr/lib/libncurses.so.5
lrwxrwxrwx 1 root root 19 May 30 2018 /usr/lib/libncurses++.so.6 -> libncurses++.so.6.1
-rwxr-xr-x 1 root root 77152 May 30 2018 /usr/lib/libncurses++.so.6.1
lrwxrwxrwx 1 root root 18 May 30 2018 /usr/lib/libncurses++w.so -> libncurses++w.so.6
-rwxr-xr-x 1 root root 531 May 30 2018 /usr/lib/libncursesw.so
-rwxr-xr-x 1 root root 349688 Jan 16 2018 /usr/lib/libncursesw.so.5
lrwxrwxrwx 1 root root 20 May 30 2018 /usr/lib/libncurses++w.so.6 -> libncurses++w.so.6.1
-rwxr-xr-x 1 root root 77152 May 30 2018 /usr/lib/libncurses++w.so.6.1
My ncurses6 looks to be almost a year old - is Ubuntu still maining 5?