Still happening in F25, when logging out of gnome wayland session.

(In reply to Don Swaner from comment #1)
> Still happening in F25, when logging out of gnome wayland session.

My usb mouse and keyboard freeze when I log out and it's always accompanied by this g_object_unref message.  There are also several 'Could not open device /dev/input/event#...' accompanying this.

Happens only my new home machine.  A Supermicro C7H170 M/B.  Vendor claims its Wayland but I have 4 other machines at work running F25 with Wayland and my previous 10 year machine without this problem.

Doesn't always happen but I'd say 4 out of 5 times, it does.  And sometimes it happens during a session.  Computer is still running because youtube music is still playing.

The common diagnositic is that the journal always reports the g_object_unref message when this happens.

As per comment 2, I am also getting a system freeze on logout sometimes.  This is also on a new machine: HP Slimline 260 with Intel HD Graphics 530. Similarly, even though the desktop is frozen, the system is actually running - e.g. cron jobs.  However, the mouse is frozen and I'm unable to switch to a console - the only fix is a cold reboot.  This is also under Wayland.  The "GLib-GObject-CRITICAL: g_object_unref: assertion 'G_IS_OBJECT (object)' failed" message is repeated about 10 times.  Also getting lots of "Could not open device /dev/input/event..." errors in the journal.  Also:

Failed to connect to missing device /org/freedesktop/ColorManager/devices/xrandr_ViewSonic_Corporation_VA902_SERIES_PSW062126411_..._1000

... org.gnome.Shell.desktop[1597]: could not connect to wayland server
... org.gnome.Shell.desktop[1597]: Fatal server error:
... org.gnome.Shell.desktop[1597]: (EE) Couldn't add screen

I seemed to have solved my freeze problem.  Vendor suggested it was a Wayland problem and to switch to Xorg.  One hour into Xorg, mouse froze again but this time the logs showed something different.  I'm sorry I did not record it down, but it appeared to point the finger at nouveau.  I  pulled the GT710 video card from the machine.  M/B comes with onboard video, part of the H170 chipset.  I've not a mouse freeze since.  I did this on 4/16.  So, 3 weeks now and with a couple handfuls of logins/logouts.

The 'g_object_unref...could not connect to wayland' log entries are still there on logouts but they appear to no longer affect the system.

One more data point:  My desktop at work, F25 Wayland, started to have mouse freezes the day after I posted.  Prior, it had run without any hiccups for a month. I pulled the same GT710 card (an EVGA) and it's also been stable since.

3 weeks is perhaps still early.  Keeping fingers crossed.

I have this problem too. I use Xorg but the computer logs:
gnome-session-b: GLib-GObject-CRITICAL: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
10 times every shout down

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I'm seeing this on a fresh F26 install using xorg but not after logout.  Not sure if it's the same issue bit resetting version to F26 to keep it on the radar.  Hey Ray, if you want to go visit my mom I'll get her to reproduce this for you ;).

I can confirm that this bug has hit RHEL 7.4
Here is the most recent messages generated:

# journalctl -b 0 | grep CRITICAL
Oct 11 07:07:40 Desktop gnome-session-binary[2861]: GLib-GObject-CRITICAL: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Oct 11 07:07:40 Desktop gnome-session[2861]: gnome-session-binary[2861]: GLib-GObject-CRITICAL: g_object_unref: assertion 'G_IS_OBJECT (object)' failed

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Approximately 4 (four) weeks from now Fedora will stop maintaining
and issuing updates for Fedora 26. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
this bug will be closed as EOL if it remains open with a Fedora  'version'
of '26'.

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plan to fix it in a currently maintained version, simply change the 'version'
to a later Fedora version.

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able to fix it before Fedora 26 is end of life. If you would still like
to see this bug fixed and are able to reproduce it against a later version
of Fedora, you are encouraged  change the 'version' to a later Fedora
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's
lifetime, sometimes those efforts are overtaken by events. Often a
more recent Fedora release includes newer upstream software that fixes
bugs or makes them obsolete.

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pranav@fedora /var/log> journalctl -b SYSLOG_IDENTIFIER=gnome-session
-- Journal begins at Fri 2021-05-21 12:34:16 +0545, ends at Sat 2021-08-07 20:57:26 +0545. --
Aug 07 20:07:23 fedora gnome-session[2253]: gnome-session-binary[2253]: WARNING: Failed to upload environment to systemd: GDBus.Error:org.freedesktop.DBus.Error.NameHasNoOwner: Name "org.freedesktop.systemd1" does not exist
Aug 07 20:07:23 fedora gnome-session[2253]: gnome-session-binary[2253]: WARNING: Failed to reset failed state of units: GDBus.Error:org.freedesktop.DBus.Error.NameHasNoOwner: Name "org.freedesktop.systemd1" does not exist
Aug 07 20:07:23 fedora gnome-session[2253]: gnome-session-binary[2253]: WARNING: Falling back to non-systemd startup procedure due to error: GDBus.Error:org.freedesktop.DBus.Error.NameHasNoOwner: Name "org.freedesktop.systemd1" does not exist
Aug 07 20:07:33 fedora gnome-session[3143]: gnome-session-binary[3143]: GnomeDesktop-WARNING: Could not create transient scope for PID 3161: GDBus.Error:org.freedesktop.DBus.Error.UnixProcessIdUnknown: Process with ID 3161 does not exist.
Aug 07 20:07:37 fedora gnome-session[3143]: gnome-session-binary[3143]: GnomeDesktop-WARNING: Could not create transient scope for PID 3499: GDBus.Error:org.freedesktop.DBus.Error.UnixProcessIdUnknown: Process with ID 3499 does not exist.
pranav@fedora /var/log>

I think after the recent gnome update (version 40.3.0), I started to see this.