Upgrade to Bookworm, Deconz works but apt throws warning

I upgraded to bookworm today and so far all works fine. However, when I carry out

sudo apt update && sudo apt full-upgrade

I get the following warning:

W: http://phoscon.de/apt/deconz/dists/bookworm/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.

What is there to do to remedy this?

Thank you for looking into it.

The warning is shown since Debian APT repositories have change how GPG keys are stored.
Note this is only informative not a problem for actual functionality.

The deCONZ APT repository currently still uses the old way since we support multiple Debian/Ubuntu versions. However I think we can move on since all supported versions should be recent enough to support the new key handling, we’ll have a look how to make this.