```
$ sudo apt-key add winehq.key
[sudo] password for aresminos: 
gpg: invalid key resource URL '/etc/apt/trusted.gpg.d/graphics:darktable:master.gpg'
gpg: keyblock resource '(null)': General error
gpg: key 040524A84C70D8B5: 1 signature not checked due to a missing key
gpg: key 3B4FE6ACC0B21F32: 3 signatures not checked due to missing keys
gpg: key D94AA3F0EFE21092: 3 signatures not checked due to missing keys
gpg: key 871920D1991BC93C: 1 signature not checked due to a missing key
gpg: key 76F1A20FF987672F: 1 signature not checked due to a missing key
gpg: Total number processed: 9
gpg:       skipped new keys: 9
```