Linux Mint officially does not support upgrades (at all). Their literal directions are to backup your data, re-install cleanly, and then restore your user file

Linux Mint officially does not support upgrades (at all). Their literal directions are to backup your data, re-install cleanly, and then restore your user files (implying it's not recommended to restore settings). Debian provides a generally well supported and documented upgrade process. However it's the sort of thing that you frequently want an expert on hand to do. Still, many people pay to have their car's oil changed.