Just updated to linux mint 21

the FDM deb package appears to be using the bionic repo

The repo should be Jammy

Does anyone know how to fix this error:?

W: https://debrepo.freedownloadmanager.org ... /InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.


The error appears when checking for updates

Edit:

After finding the man page regarding the issue, apt key will be removed in the next release thus a security change was made. If anyone is using LM 21, you will need to use method 2 described here
https://www.omgubuntu.co.uk/2022/06/fix-apt-key-deprecation-error-on-ubuntu

Method 1 won't work with LM 21