When updating via apt-get on Ubuntu 16.04 I get an error message saying:
Err:20 http://downloads.skewed.de/apt/xenial xenial Release.gpg
The following signatures couldn't be verified because the public key is
not available: NO_PUBKEY 78AF38AD52B46290
Re-adding the keys as outlined in the installation instructions seems to fix
the problem but I wanted to check if this was expected behaviour.
Thanks for any advice in advance.