I just upgraded from Ubuntu 21.10 to 22.04.
sudo apt update
ends with the following warnings...
W: https://linux.teamviewer.com/deb/dists/stable/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://apt.keepsolid.com/ubuntu/dists/groovy/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://linux.dropbox.com/ubuntu/dists/disco/Release.gpg: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://download.virtualbox.org/virtualbox/debian/dists/hirsute/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://download.opensuse.org/repositories/home:/IBBoard:/cawbird/xUbuntu_22.04/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://ppa.launchpad.net/solaar-unifying/stable/ubuntu/dists/jammy/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://ppa.launchpad.net/team-xbmc/ppa/ubuntu/dists/jammy/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
W: http://ppa.launchpad.net/yannubuntu/boot-repair/ubuntu/dists/jammy/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
Synaptic
shows the same warnings on a reload.
Reviewing man apt-key
doesn't clarify this for me.
I think this is because Ubuntu 22.04 has transitioned from using /etc/apt/trusted.gpg to using individual .gpg files located in /etc/apt/trusted.gpg.d.
Can these keys be converted from one to the other, or must I delete these keys and reimport them?