The package I need (https://ubuntu.pkgs.org/20.10/ubuntu-main-amd64/gir1.2-ecal-2.0_3.38.1-1_amd64.deb.html) is not available in Zorin OS repos but is present in Ubuntu Groovy main. Is it safe to add that repo to sources.list file and then download the package or is there a better way to go about this? My concern is that current Zorin OS is based on an older version of Ubuntu (bionic) and that adding Groovy's repo might break things..
Thanks
This is a tough question. It might be safe to do so, for that some specific packages only. If it works, you will probably need to remove that Groovy repo afterward so that it does not mess up your other Bionic packages.
That said, that package you are referring to in this case deals with other Shared Object files. The Groovy Release may not be compatible with your current Bionic packages.
So rather than using the repository, you could just download the .deb package and install it by double clicking it from your Downloads folder:
archive.ubuntu.com/ubuntu/pool/main/e/evolution-data-server/gir1.2-ecal-2.0_3.38.1-1_amd64.deb
No guarantees that it will work properly on Bionic. Please be sure to make thorough system back ups before testing.