How to fix "Key is stored in legacy trusted.gpg keyring" apt error in Ubuntu and Debian - the right way
If you use a recent version of Debian, Ubuntu or one of their derivatives, and you added a PPA or followed instructions found online for adding an external repository to your system, you may have seen a warning like the following:
W: http://ppa.launchpad.net/git-core/ppa/ubuntu: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
Here’s the right way fix it.
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