No, really, the text is right - kubuntu-restricted-extras *source* package no longer exists.
% apt-cache showsrc ubuntu-restricted-extras | grep Binary Binary: ubuntu-restricted-extras, kubuntu-restricted-extras, xubuntu-restricted-extras
Reassigning to the source package that *does* exist.
No, really, the text is right - kubuntu- restricted- extras *source* package no longer exists.
% apt-cache showsrc ubuntu- restricted- extras | grep Binary restricted- extras, kubuntu- restricted- extras, xubuntu- restricted- extras
Binary: ubuntu-
Reassigning to the source package that *does* exist.