There is no longer support for 8 bit color depth in TigerVNC (see:
https://github.com/TigerVNC/tigervnc/commit/e86d8720ba1e79b486ca29a5c2b27fa25811e6a2);
using it causes a fatal error.

Submitted upstream at: https://github.com/canonical/lightdm/pull/265.

diff --git a/data/lightdm.conf b/data/lightdm.conf
index 0df38429..60e3e8b4 100644
--- a/data/lightdm.conf
+++ b/data/lightdm.conf
@@ -160,4 +160,4 @@
 #listen-address=
 #width=1024
 #height=768
-#depth=8
+#depth=24
diff --git a/src/x-server-xvnc.c b/src/x-server-xvnc.c
index 68340d53..27ca4454 100644
--- a/src/x-server-xvnc.c
+++ b/src/x-server-xvnc.c
@@ -127,7 +127,7 @@ x_server_xvnc_init (XServerXVNC *server)
     XServerXVNCPrivate *priv = x_server_xvnc_get_instance_private (server);
     priv->width = 1024;
     priv->height = 768;
-    priv->depth = 8;
+    priv->depth = 24;
 }
 
 static void
diff --git a/tests/scripts/vnc-command.conf b/tests/scripts/vnc-command.conf
index 0f1e25fd..335956d9 100644
--- a/tests/scripts/vnc-command.conf
+++ b/tests/scripts/vnc-command.conf
@@ -19,7 +19,7 @@ command=Xvnc -option
 #?VNC-CLIENT CONNECT
 
 # Xvnc server starts
-#?XVNC-0 START GEOMETRY=1024x768 DEPTH=8 OPTION=TRUE
+#?XVNC-0 START GEOMETRY=1024x768 DEPTH=24 OPTION=TRUE
 
 # Daemon connects when X server is ready
 #?*XVNC-0 INDICATE-READY
diff --git a/tests/scripts/vnc-guest.conf b/tests/scripts/vnc-guest.conf
index 431bb244..ce2b97db 100644
--- a/tests/scripts/vnc-guest.conf
+++ b/tests/scripts/vnc-guest.conf
@@ -21,7 +21,7 @@ user-session=default
 #?VNC-CLIENT CONNECT
 
 # Xvnc server starts
-#?XVNC-0 START GEOMETRY=1024x768 DEPTH=8 OPTION=FALSE
+#?XVNC-0 START GEOMETRY=1024x768 DEPTH=24 OPTION=FALSE
 
 # Daemon connects when X server is ready
 #?*XVNC-0 INDICATE-READY
diff --git a/tests/scripts/vnc-login.conf b/tests/scripts/vnc-login.conf
index cdfe17b8..f0d65b7f 100644
--- a/tests/scripts/vnc-login.conf
+++ b/tests/scripts/vnc-login.conf
@@ -21,7 +21,7 @@ user-session=default
 #?VNC-CLIENT CONNECT
 
 # Xvnc server starts
-#?XVNC-0 START GEOMETRY=1024x768 DEPTH=8 OPTION=FALSE
+#?XVNC-0 START GEOMETRY=1024x768 DEPTH=24 OPTION=FALSE
 
 # Daemon connects when X server is ready
 #?*XVNC-0 INDICATE-READY
diff --git a/tests/scripts/vnc-open-file-descriptors.conf b/tests/scripts/vnc-open-file-descriptors.conf
index 753c84dd..e5d35730 100644
--- a/tests/scripts/vnc-open-file-descriptors.conf
+++ b/tests/scripts/vnc-open-file-descriptors.conf
@@ -21,7 +21,7 @@ user-session=default
 #?VNC-CLIENT CONNECT
 
 # Xvnc server starts
-#?XVNC-0 START GEOMETRY=1024x768 DEPTH=8 OPTION=FALSE
+#?XVNC-0 START GEOMETRY=1024x768 DEPTH=24 OPTION=FALSE
 
 # Daemon connects when X server is ready
 #?*XVNC-0 INDICATE-READY
2023-05-11 13:21:45 +0200'>2023-05-11</span></td><td><a href='/guix/commit/gnu/services/lightdm.scm?id=2df5d4fd18a2fbcb8066a50e2da8ec64635f5162'>system: pam: Let PAM extensions add shepherd requirements.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/pam.scm (&lt;pam-extension&gt;): New record type.
(pam-shepherd-service): Add Shepherd synchronization point.

* gnu/services/mail.scm (dovecot-shepherd-service)
* gnu/services/lightdm.scm (lightdm-shepherd-service)
* gnu/services/mail.scm (opensmtpd-shepherd-service)
* gnu/services/sddm.scm (sddm-shepherd-service)
* gnu/services/ssh.scm (lsh-shepherd-service, openssh-shepherd-service)
* gnu/services/xorg.scm (slim-shepherd-service, gdm-shepherd-service)
* gnu/services/base.scm (greetd-shepherd-services): Add PAM requirement.

* gnu/system/pam.scm (/etc-entry, extend-configuration,
pam-root-service-type, pam-root-service)
* gnu/services/authentication.scm (pam-ldap-pam-service)
* gnu/services/base.scm (pam-limits-service-type)
(greetd-pam-service)
* gnu/services/desktop.scm (pam-gnome-keyring)
* gnu/services/kerberos.scm (pam-krb5-pam-service)
* gnu/services/pam-mount.scm (pam-mount-pam-service): Adapt to use
pam-extension.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Josselin Poiret</td></tr>
<tr><td><span title='2023-02-08 22:40:40 -0500'>2023-02-08</span></td><td><a href='/guix/commit/gnu/services/lightdm.scm?id=8a2c2eaa906bd12d9c804ba18ac305b9719507ef'>services: lightdm: Sync documentation with source.</a><span class='msg-avail'>...<span class='msg-tooltip'>Table entry @item nodes cannot span multiple lines.

* gnu/services/lightdm.scm
(lightdm-gtk-greeter-configuration): Fix cursor-theme-size description.
* doc/guix.texi (lightdm-service-type): Sync with source.

Signed-off-by: Maxim Cournoyer &lt;maxim.cournoyer@gmail.com&gt;
</span></span></td><td>Bruno Victal</td></tr>