Description:

when start a vnc server by "systemctl start vncserver@:1", the xfce4-session will crash.

Oct 22 11:25:12 xxx-mpc audit[15888]: ANOM_ABEND auid=1000 uid=1000 gid=1000 ses=29 pid=15888 comm="xfce4-session" exe="/usr/bin/xfce4-session" sig=11 res=1
Oct 22 11:25:12 xxx-mpc systemd[1]: Started Process Core Dump (PID 15918/UID 0).
Oct 22 11:25:12 xxx-mpc audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-coredump@20-15918-0 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
Oct 22 11:25:14 xxx-mpc systemd-coredump[15919]: [🡕] Process 15888 (xfce4-session) of user 1000 dumped core.

Stack trace of thread 15888:
#0 0x000055a4fb0e6a70 xfsm_manager_get_shutdown_type (xfce4-session + 0x24a70)
#1 0x000055a4fb0d9c38 n/a (xfce4-session + 0x17c38)
#2 0x00007f09d735188f n/a (libgio-2.0.so.0 + 0xf888f)
#3 0x00007f09d7359398 n/a (libgio-2.0.so.0 + 0x100398)
#4 0x00007f09d72fa0f4 n/a (libgio-2.0.so.0 + 0xa10f4)
#5 0x00007f09d72fe639 n/a (libgio-2.0.so.0 + 0xa5639)
#6 0x00007f09d7353340 n/a (libgio-2.0.so.0 + 0xfa340)
#7 0x00007f09d72fa0f4 n/a (libgio-2.0.so.0 + 0xa10f4)
#8 0x00007f09d72fa129 n/a (libgio-2.0.so.0 + 0xa1129)
#9 0x00007f09d7123b00 g_main_context_dispatch (libglib-2.0.so.0 + 0x52b00)
#10 0x00007f09d71751f9 n/a (libglib-2.0.so.0 + 0xa41f9)
#11 0x00007f09d7123163 g_main_loop_run (libglib-2.0.so.0 + 0x52163)
#12 0x00007f09d78fc21f gtk_main (libgtk-3.so.0 + 0x1e021f)
#13 0x000055a4fb0d417f main (xfce4-session + 0x1217f)
#14 0x00007f09d6f0c152 __libc_start_main (libc.so.6 + 0x28152)
#15 0x000055a4fb0d43ee _start (xfce4-session + 0x123ee)

Stack trace of thread 15907:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b08e04 n/a (swrast_dri.so + 0x640e04)
#2 0x00007f09d4b00b18 n/a (swrast_dri.so + 0x638b18)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15903:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b21584 n/a (swrast_dri.so + 0x659584)
#2 0x00007f09d4b00b48 n/a (swrast_dri.so + 0x638b48)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15909:
#0 0x00007f09d6fd946f __poll (libc.so.6 + 0xf546f)
#1 0x00007f09d7175188 n/a (libglib-2.0.so.0 + 0xa4188)
#2 0x00007f09d7122421 g_main_context_iteration (libglib-2.0.so.0 + 0x51421)
#3 0x00007f09d7122472 n/a (libglib-2.0.so.0 + 0x51472)
#4 0x00007f09d7150a91 n/a (libglib-2.0.so.0 + 0x7fa91)
#5 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#6 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15901:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b21584 n/a (swrast_dri.so + 0x659584)
#2 0x00007f09d4b00b48 n/a (swrast_dri.so + 0x638b48)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15906:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b08e04 n/a (swrast_dri.so + 0x640e04)
#2 0x00007f09d4b00b18 n/a (swrast_dri.so + 0x638b18)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15902:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b21584 n/a (swrast_dri.so + 0x659584)
#2 0x00007f09d4b00b48 n/a (swrast_dri.so + 0x638b48)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15910:
#0 0x00007f09d6fd946f __poll (libc.so.6 + 0xf546f)
#1 0x00007f09d7175188 n/a (libglib-2.0.so.0 + 0xa4188)
#2 0x00007f09d7123163 g_main_loop_run (libglib-2.0.so.0 + 0x52163)
#3 0x00007f09d735afe8 n/a (libgio-2.0.so.0 + 0x101fe8)
#4 0x00007f09d7150a91 n/a (libglib-2.0.so.0 + 0x7fa91)
#5 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#6 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15908:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b08e04 n/a (swrast_dri.so + 0x640e04)
#2 0x00007f09d4b00b18 n/a (swrast_dri.so + 0x638b18)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15904:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b21584 n/a (swrast_dri.so + 0x659584)
#2 0x00007f09d4b00b48 n/a (swrast_dri.so + 0x638b48)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15905:
#0 0x00007f09d70be6a2 pthread_cond_wait@@GLIBC_2.3.2 (libpthread.so.0 + 0xf6a2)
#1 0x00007f09d4b08e04 n/a (swrast_dri.so + 0x640e04)
#2 0x00007f09d4b00b18 n/a (swrast_dri.so + 0x638b18)
#3 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#4 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)

Stack trace of thread 15911:
#0 0x00007f09d6fded5d syscall (libc.so.6 + 0xfad5d)
#1 0x00007f09d71710cb g_cond_wait_until (libglib-2.0.so.0 + 0xa00cb)
#2 0x00007f09d70f3833 n/a (libglib-2.0.so.0 + 0x22833)
#3 0x00007f09d715376b n/a (libglib-2.0.so.0 + 0x8276b)
#4 0x00007f09d7150a91 n/a (libglib-2.0.so.0 + 0x7fa91)
#5 0x00007f09d70b83e9 start_thread (libpthread.so.0 + 0x93e9)
#6 0x00007f09d6fe4293 __clone (libc.so.6 + 0x100293)
Oct 22 11:25:14 xxx-mpc systemd[1]: systemd-coredump@20-15918-0.service: Succeeded.

Additional info:
* package version(s)
xfce4-session-4.14.2-2
* config and/or log files etc.
normal config
* link to upstream bug report, if any
https://gitlab.xfce.org/xfce/xfce4-session/-/issues/54

Steps to reproduce: