Snap is a package management system for installing and managing the applications (called Snaps) developed by Cananoical for Linux operating systems. The Snap is a bundle of an app and its dependencies that work across many different Linux distributions.
The snapd manages the snap environment on the local system, and it discovers the application (snaps) from the Snap Store and installs it on the system.
Why Snap is blocked On Linux Mint 20
In May 2020 edition of the Linux Mint blog news, Linux Mint community announced that Linux Mint 20 would forbid the installation of snapd package via the APT package manager.
That is the reason you are getting the below message when you try to install the Snap on Linux Mint 20.
Reading package lists... Done Building dependency tree Reading state information... Done Package snapd is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package 'snapd' has no installation candidate
This decision was taken due to Canonical’s decision to change the method of installing the Chromium web browser from APT to Snap as Linux Mint has no control of Snap store packages.
As per the blog,
A year later, in the Ubuntu 20.04 package base, the Chromium package is indeed empty and acting, without your consent, as a backdoor by connecting your computer to the Ubuntu Store. Applications in this store cannot be patched, or pinned. You can’t audit them, hold them, modify them or even point snap to a different store. You’ve as much empowerment with this as if you were using proprietary software, i.e. none. This is in effect similar to a commercial proprietary solution, but with two major differences: It runs as root, and it installs itself without asking you.
Enable Snap On Linux Mint 20
If you still want to use the Snap package manager on Linux Mint 20, you can do that by re-enabling and installing it by following the below steps.
sudo rm /etc/apt/preferences.d/nosnap.pref
Update the repository index.
sudo apt update
Install the Snap package manager with the following command.
sudo apt install -y snapd
Check the version of Snap.
snap version
Output:
snap 2.45.1+20.04 snapd 2.45.1+20.04 series 16 linuxmint 20 kernel 4.15.0-20-generic
Conclusion
That’s All.