Digging around a bit, this is likely the info you did not really want to read:
https://forum.sailfishos.org/t/patch...-in-koli-4-0-1
tl;dr
Patchmanager is not working on 4.0 but possibly fixable by installing a different busybox-symlinks-bash afaiu.
But i am not eager to try since my setup runs nicely and i fear to break things :P