I’m running Arch and have the same problem on my desktop pc only (not my laptop).
$ pacman -Q | grep plasma.*login
plasma-login-manager 6.6.4-1
$ pacman -Q | grep qt6-base
qt6-base 6.11.0-2
$ sudo systemctl get-default
graphical.target
Stack trace:
Process 946 (plasma-login-gr) of user 955 dumped core.
Stack trace of thread 946:
#0 0x00007f40424178e4 _ZNK7QWindow6screenEv (libQt6Gui.so.6 + 0x2178e4)
#1 0x000055f9dd87f32e n/a (/usr/lib/plasma-login-greeter + 0xe32e)
#2 0x00007f4041bdc9c2 n/a (libQt6Core.so.6 + 0x1dc9c2)
#3 0x00007f404242c182 _ZN22QWindowSystemInterface19handleScreenRemovedEP15QPlatformScreen (libQt6Gui.so.6 + 0x22c182)
#4 0x00007f40419653cc _ZN15QtWaylandClient15QWaylandDisplay23handleScreenInitializedEPNS_14QWaylandScreenE (libQt6WaylandClient.so.6 + 0x753cc)
#5 0x00007f40419922c6 _ZN15QtWaylandClient14QWaylandScreen15maybeInitializeEv (libQt6WaylandClient.so.6 + 0xa22c6)
#6 0x00007f403ef40ac6 n/a (libffi.so.8 + 0x7ac6)
#7 0x00007f403ef3d76b n/a (libffi.so.8 + 0x476b)
#8 0x00007f403ef4006e ffi_call (libffi.so.8 + 0x706e)
#9 0x00007f4043d5f48d n/a (libwayland-client.so.0 + 0x448d)
#10 0x00007f4043d602e9 n/a (libwayland-client.so.0 + 0x52e9)
#11 0x00007f4043d606f3 wl_display_dispatch_queue_pending (libwayland-client.so.0 + 0x56f3)
#12 0x00007f404195ed76 _ZN15QtWaylandClient15QWaylandDisplay13flushRequestsEv (libQt6WaylandClient.so.6 + 0x6ed76)
#13 0x00007f4041bd4614 _ZN7QObject5eventEP6QEvent (libQt6Core.so.6 + 0x1d4614)
#14 0x00007f4041b76c98 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x176c98)
#15 0x00007f4041b77070 _ZN23QCoreApplicationPrivate16sendPostedEventsEP7QObjectiP11QThreadData (libQt6Core.so.6 + 0x177070)
#16 0x00007f4041e75d98 n/a (libQt6Core.so.6 + 0x475d98)
#17 0x00007f403fb06f4d n/a (libglib-2.0.so.0 + 0x5ef4d)
#18 0x00007f403fb08607 n/a (libglib-2.0.so.0 + 0x60607)
#19 0x00007f403fb08815 g_main_context_iteration (libglib-2.0.so.0 + 0x60815)
#20 0x00007f4041e72222 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x472222)
#21 0x00007f4041b845d6 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt6Core.so.6 + 0x1845d6)
#22 0x00007f4041b7a311 _ZN16QCoreApplication4execEv (libQt6Core.so.6 + 0x17a311)
#23 0x000055f9dd87cbbb n/a (/usr/lib/plasma-login-greeter + 0xbbbb)
#24 0x00007f40414366c1 n/a (libc.so.6 + 0x276c1)
#25 0x00007f40414367f9 __libc_start_main (libc.so.6 + 0x277f9)
#26 0x000055f9dd87cee5 n/a (/usr/lib/plasma-login-greeter + 0xbee5)
Stack trace of thread 988:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a23e4 n/a (libc.so.6 + 0x933e4)
#3 0x00007f404151c2f6 ppoll (libc.so.6 + 0x10d2f6)
#4 0x00007f403fb08734 n/a (libglib-2.0.so.0 + 0x60734)
#5 0x00007f403fb08815 g_main_context_iteration (libglib-2.0.so.0 + 0x60815)
#6 0x00007f4041e72222 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x472222)
#7 0x00007f4041b845d6 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt6Core.so.6 + 0x1845d6)
#8 0x00007f4041c9efa2 _ZN7QThread4execEv (libQt6Core.so.6 + 0x29efa2)
#9 0x00007f4042c2d50e n/a (libQt6DBus.so.6 + 0x3750e)
#10 0x00007f4041d4d483 n/a (libQt6Core.so.6 + 0x34d483)
#11 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#12 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 992:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f4041d50e80 _ZN14QWaitCondition4waitEP6QMutex14QDeadlineTimer (libQt6Core.so.6 + 0x350e80)
#5 0x00007f404195eec9 n/a (libQt6WaylandClient.so.6 + 0x6eec9)
#6 0x00007f4041d4d483 n/a (libQt6Core.so.6 + 0x34d483)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1010:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1011:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1004:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
Process 946 (plasma-login-gr) of user 955 dumped core.
Stack trace of thread 946:
#0 0x00007f40424178e4 _ZNK7QWindow6screenEv (libQt6Gui.so.6 + 0x2178e4)
#1 0x000055f9dd87f32e n/a (/usr/lib/plasma-login-greeter + 0xe32e)
#2 0x00007f4041bdc9c2 n/a (libQt6Core.so.6 + 0x1dc9c2)
#3 0x00007f404242c182 _ZN22QWindowSystemInterface19handleScreenRemovedEP15QPlatformScreen (libQt6Gui.so.6 + 0x22c182)
#4 0x00007f40419653cc _ZN15QtWaylandClient15QWaylandDisplay23handleScreenInitializedEPNS_14QWaylandScreenE (libQt6WaylandClient.so.6 + 0x753cc)
#5 0x00007f40419922c6 _ZN15QtWaylandClient14QWaylandScreen15maybeInitializeEv (libQt6WaylandClient.so.6 + 0xa22c6)
#6 0x00007f403ef40ac6 n/a (libffi.so.8 + 0x7ac6)
#7 0x00007f403ef3d76b n/a (libffi.so.8 + 0x476b)
#8 0x00007f403ef4006e ffi_call (libffi.so.8 + 0x706e)
#9 0x00007f4043d5f48d n/a (libwayland-client.so.0 + 0x448d)
#10 0x00007f4043d602e9 n/a (libwayland-client.so.0 + 0x52e9)
#11 0x00007f4043d606f3 wl_display_dispatch_queue_pending (libwayland-client.so.0 + 0x56f3)
#12 0x00007f404195ed76 _ZN15QtWaylandClient15QWaylandDisplay13flushRequestsEv (libQt6WaylandClient.so.6 + 0x6ed76)
#13 0x00007f4041bd4614 _ZN7QObject5eventEP6QEvent (libQt6Core.so.6 + 0x1d4614)
#14 0x00007f4041b76c98 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x176c98)
#15 0x00007f4041b77070 _ZN23QCoreApplicationPrivate16sendPostedEventsEP7QObjectiP11QThreadData (libQt6Core.so.6 + 0x177070)
#16 0x00007f4041e75d98 n/a (libQt6Core.so.6 + 0x475d98)
#17 0x00007f403fb06f4d n/a (libglib-2.0.so.0 + 0x5ef4d)
#18 0x00007f403fb08607 n/a (libglib-2.0.so.0 + 0x60607)
#19 0x00007f403fb08815 g_main_context_iteration (libglib-2.0.so.0 + 0x60815)
#20 0x00007f4041e72222 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x472222)
#21 0x00007f4041b845d6 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt6Core.so.6 + 0x1845d6)
#22 0x00007f4041b7a311 _ZN16QCoreApplication4execEv (libQt6Core.so.6 + 0x17a311)
#23 0x000055f9dd87cbbb n/a (/usr/lib/plasma-login-greeter + 0xbbbb)
#24 0x00007f40414366c1 n/a (libc.so.6 + 0x276c1)
#25 0x00007f40414367f9 __libc_start_main (libc.so.6 + 0x277f9)
#26 0x000055f9dd87cee5 n/a (/usr/lib/plasma-login-greeter + 0xbee5)
Stack trace of thread 988:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a23e4 n/a (libc.so.6 + 0x933e4)
#3 0x00007f404151c2f6 ppoll (libc.so.6 + 0x10d2f6)
#4 0x00007f403fb08734 n/a (libglib-2.0.so.0 + 0x60734)
#5 0x00007f403fb08815 g_main_context_iteration (libglib-2.0.so.0 + 0x60815)
#6 0x00007f4041e72222 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x472222)
#7 0x00007f4041b845d6 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt6Core.so.6 + 0x1845d6)
#8 0x00007f4041c9efa2 _ZN7QThread4execEv (libQt6Core.so.6 + 0x29efa2)
#9 0x00007f4042c2d50e n/a (libQt6DBus.so.6 + 0x3750e)
#10 0x00007f4041d4d483 n/a (libQt6Core.so.6 + 0x34d483)
#11 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#12 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 992:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f4041d50e80 _ZN14QWaitCondition4waitEP6QMutex14QDeadlineTimer (libQt6Core.so.6 + 0x350e80)
#5 0x00007f404195eec9 n/a (libQt6WaylandClient.so.6 + 0x6eec9)
#6 0x00007f4041d4d483 n/a (libQt6Core.so.6 + 0x34d483)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1010:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1011:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1004:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1012:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 993:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a23e4 n/a (libc.so.6 + 0x933e4)
#3 0x00007f404151bdae __poll (libc.so.6 + 0x10cdae)
#4 0x00007f404195ef30 n/a (libQt6WaylandClient.so.6 + 0x6ef30)
#5 0x00007f4041d4d483 n/a (libQt6Core.so.6 + 0x34d483)
#6 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#7 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1018:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1017:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1114:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1204:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a23e4 n/a (libc.so.6 + 0x933e4)
#3 0x00007f404151c2f6 ppoll (libc.so.6 + 0x10d2f6)
#4 0x00007f403fb08734 n/a (libglib-2.0.so.0 + 0x60734)
#5 0x00007f403fb08815 g_main_context_iteration (libglib-2.0.so.0 + 0x60815)
#6 0x00007f4041e72222 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x472222)
#7 0x00007f4041b845d6 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE (libQt6Core.so.6 + 0x1845d6)
#8 0x00007f4041c9efa2 _ZN7QThread4execEv (libQt6Core.so.6 + 0x29efa2)
#9 0x00007f4041d4d483 n/a (libQt6Core.so.6 + 0x34d483)
#10 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#11 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
Stack trace of thread 1016:
#0 0x00007f40414adf32 n/a (libc.so.6 + 0x9ef32)
#1 0x00007f40414a239c n/a (libc.so.6 + 0x9339c)
#2 0x00007f40414a268c n/a (libc.so.6 + 0x9368c)
#3 0x00007f40414a4e5e pthread_cond_wait (libc.so.6 + 0x95e5e)
#4 0x00007f40291eca1e n/a (libgallium-26.0.4-arch1.1.so + 0x5eca1e)
#5 0x00007f40291a1dbd n/a (libgallium-26.0.4-arch1.1.so + 0x5a1dbd)
#6 0x00007f40291ec95d n/a (libgallium-26.0.4-arch1.1.so + 0x5ec95d)
#7 0x00007f40414a597a n/a (libc.so.6 + 0x9697a)
#8 0x00007f40415292bc n/a (libc.so.6 + 0x11a2bc)
ELF object binary architecture: AMD x86-64