Bug#1051695: gdm3: 150% fractional scale not working after upgrade from gdm3 44 to 45

[Eni]

Package: gdm3
Version: 45~beta-1
Severity: normal
X-Debbugs-Cc: enigma at petalmail.com

Dear Maintainer,

  After upgrade gdm3 from 44 to 45~beta-1, the fractional scale of gdm not fully working.

  I set up fractional scale following steps below:

  1. sudo cp ~/.config/monitors.xml /var/lib/gdm3/.config/monitors.xml
  2. sudo chown Debian-gdm:Debian-gdm /var/lib/gdm3/.config/monitors.xml
  3. sudo machinectl shell Debian-gdm@ /bin/bash
  4. gsettings set org.gnome.mutter experimental-features "['scale-monitor-framebuffer']"

  I set it for 150% scale, and the fractional scale works fine in gnome 43 and 44.

  Recently the gdm3 upgraded to 45~beta-1, I found the scale of gdm doesn't work anymore. 
I tried to figure out what is going on, so I installed a clean copy of Debian unstable, 
and reproduced problem:

  gdm3:45~beta-1:

  * set scale for 150%: gdm3 fall to 100% scale
  * set scale for 250%: gdm3 works with 250% scale

  So it seems not the scale not working completely, the scale just not working at 150%.

  Thank you.


-- System Information:
Debian Release: trixie/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 6.4.0-4-amd64 (SMP w/4 CPU threads; PREEMPT)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages gdm3 depends on:
ii  accountsservice                       23.13.9-4
ii  adduser                               3.137
ii  dbus [default-dbus-system-bus]        1.14.10-1
ii  dbus-bin                              1.14.10-1
ii  dbus-daemon                           1.14.10-1
ii  dconf-cli                             0.40.0-4
ii  dconf-gsettings-backend               0.40.0-4
ii  debconf [debconf-2.0]                 1.5.82
ii  gir1.2-gdm-1.0                        45~beta-1
ii  gnome-console [x-terminal-emulator]   45~beta-2
ii  gnome-session [x-session-manager]     44.0-4
ii  gnome-session-bin                     44.0-4
ii  gnome-session-common                  44.0-4
ii  gnome-settings-daemon                 45~rc-1
ii  gnome-shell                           44.4-1
ii  gnome-terminal [x-terminal-emulator]  3.49.99-1
ii  gsettings-desktop-schemas             45~rc-1
ii  libaccountsservice0                   23.13.9-4
ii  libaudit1                             1:3.1.1-1
ii  libc6                                 2.37-8
ii  libcanberra-gtk3-0                    0.30-10
ii  libcanberra0                          0.30-10
ii  libgdk-pixbuf-2.0-0                   2.42.10+dfsg-1+b1
ii  libgdm1                               45~beta-1
ii  libglib2.0-0                          2.78.0-1
ii  libglib2.0-bin                        2.78.0-1
ii  libgtk-3-0                            3.24.38-5
ii  libgudev-1.0-0                        238-2
ii  libkeyutils1                          1.6.3-2
ii  libpam-modules                        1.5.2-7
ii  libpam-runtime                        1.5.2-7
ii  libpam-systemd [logind]               254.1-3
ii  libpam0g                              1.5.2-7
ii  librsvg2-common                       2.54.7+dfsg-2
ii  libselinux1                           3.5-1
ii  libsystemd0                           254.1-3
ii  libx11-6                              2:1.8.6-1
ii  libxau6                               1:1.0.9-1
ii  libxcb1                               1.15-1
ii  libxdmcp6                             1:1.1.2-3
ii  polkitd                               123-1
ii  procps                                2:4.0.3-1
ii  systemd-sysv                          254.1-3
ii  ucf                                   3.0043+nmu1
ii  x11-common                            1:7.7+23
ii  x11-xserver-utils                     7.7+9+b1

Versions of packages gdm3 recommends:
ii  at-spi2-core                       2.49.91-2
ii  desktop-base                       12.0.6+nmu1
ii  gnome-session [x-session-manager]  44.0-4
ii  x11-xkb-utils                      7.7+7
ii  xserver-xephyr                     2:21.1.8-1
ii  xserver-xorg                       1:7.7+23
ii  zenity                             3.44.2-1

Versions of packages gdm3 suggests:
pn  libpam-fprintd        <none>
ii  libpam-gnome-keyring  42.1-1+b2
pn  libpam-pkcs11         <none>
pn  libpam-sss            <none>
pn  orca                  <none>

-- debconf information:
  gdm3/daemon_name: /usr/sbin/gdm3
* shared/default-x-display-manager: gdm3