Then tried to install mint-meta-debian-cinnamon since my desktop is cinnamon (no mate). This failed with the message:
Depends xchat, but it is not going to be install. You have held broken packages
Not sure how to resolve this?
NOTE: originally posted to update/upgrade, then saw that this was probably the correct forum. Will try to delete the first post, but notice that someone has replied saying he had the same issue. Sorry.