Can I upgrade Coconut to Mint?

[Linux for blind general discussion]

In theory, since both are Debian based systems using dpkg and apt, you
could add the mint repositories to your /etc/apt/sources.list and then
run:

sudo apt-get update
sudo apt-get upgrade

and all of your installed packages would be upgraded to the newest
version provided by Mint.

In practice, you'd likely end up with a mix of packages sourced from
both, even if you also removed the Coconut repositories since the Mint
version of a package would only be installed if it's version number
parses as higher to apt... but worse, you might run into conflicts
where a package sourced from Coconut depends on one version of a
Library and a Package from Mint depends on a different version of the
same library, you can't have both versions of the library installed at
the same time, and you end up with a tangled mess that in order to
upgrade some packages you must downgrade or remove other packages or
swap a package that was installed as a dependency for an alternative
package that meets the same dependency... Granted, such problems can
come up when  upgrading from one release to another of the same
distro, especially if there's an intermediate release(say, trying to
go from Ubuntu 20.10 directly to 21.10 instead of upgrading to 21.04
first), or even within the same release of a distro if the release
gets frequent upgrades to individual packages and you go a long time
without upgrading, but competent package maintenance can keep this to
a minimum as long as you stick to one distro...

As such, it's generally recommended that one does a clean install if
they want to switch distros, even for distros that are very closely
related.

That said, if you have a separate /home partition, you might be able
to migrate user setting simply by leaving the /home partition alone
and creating a user with the same username as the old distro, and
while it won't give you afull list of installed packages(which might
not be all that useful, since some will be libraries that might not
exist in the distro you're switching to, if you install the deborphan
package and run

deborphan -a

It'll give you a list of installed packages that aren't depended on by
other packages. They'll be prefixed with their section and one per
line, but strip away the former and put them all on one line, and
you've got the argument list to feed to apt-get install on the new
distro to restore most of your installed software.