After upgrade from 23.04 to 23.10 I now have a black screen background

[Chris Green]

I recently used do-release-upgrade to upgrade my Lenovo T470 from
[x]ubuntu 23.04 to [x]ubuntu 23.10.

It's working OK but permission changes on the /run/NetworkManager
directory have broken one bit of customisation.  The permissions on
/run/NetworkManager used to be:-

    chris$ ls -l /run
    total 36
    drwxr-xr-x  5 root              root     140 Dec 15 16:24 NetworkManager
    srw-rw-rw-  1 root              root       0 Dec 15 13:20 acpid.socket
    -rw-------  1 root              root       0 Dec 15 13:20 agetty.reload
    drwxr-xr-x  2 root              root      40 Dec 15 13:20 alsa
    drwxr-xr-x  3 root              root      80 Dec 15 13:20 apache2
    drwxr-xr-x  2 avahi             avahi     80 Dec 15 13:20 avahi-daemon
    ...
    ...


Now they are:-

    chris$ ls -l /run
    total 36
    drwx------  5 root              root     140 Dec 15 16:24 NetworkManager
    srw-rw-rw-  1 root              root       0 Dec 15 13:20 acpid.socket
    -rw-------  1 root              root       0 Dec 15 13:20 agetty.reload
    drwxr-xr-x  2 root              root      40 Dec 15 13:20 alsa
    drwxr-xr-x  3 root              root      80 Dec 15 13:20 apache2
    drwxr-xr-x  2 avahi             avahi     80 Dec 15 13:20 avahi-daemon
    ...
    ...

Can anyone tell me where these permissions are configured, or even if
they are 'configured' at all and not just set by code in NetworkManager.

I use the file /run/NetworkManager/no-stub-resolv.conf in my dnsmasq
configuration so it needs read access to that dirctory.  It's the
different upstream DNS server I need, when on my home LAN dnsmasq uses
the LAN DNS server but when away from the LAN it gets the DNS servers
provided by whatever means Im using to connect to the 'net.

Alternatively is there a simple way to find out (as NetworkManager
does) what upstream DNS server to use?

-- 
Chris Green