Here is another call stack with a crash:

Thread 1 "kamoso" received signal SIGSEGV, Segmentation fault.
g_type_check_instance_is_fundamentally_a (type_instance=0x5555563169b0, fundamental_type=0x50 [None]) at ../../../gobject/gtype.c:4167
Downloading source file /usr/src/glib2.0-2.76.3-1ubuntu1/debian/build/deb/../../../gobject/gtype.c
4167      return node && (NODE_FUNDAMENTAL_TYPE(node) == fundamental_type);                                                                                                        
(gdb) up
#1  0x00007ffff6eecfac in g_object_notify (object=0x5555563169b0, property_name=0x7fffd80c6901 "zoom") at ../../../gobject/gobject.c:1584
1584      g_return_if_fail (G_IS_OBJECT (object));                                                                                                                                 
(gdb) up
#2  0x00007ffff6edc010 in g_closure_invoke (closure=0x55555645bad0, return_value=0x0, n_param_values=2, param_values=0x7fffffffcb80, invocation_hint=0x7fffffffcb00)
    at ../../../gobject/gclosure.c:832
Downloading source file /usr/src/glib2.0-2.76.3-1ubuntu1/debian/build/deb/../../../gobject/gclosure.c
u832          marshal (closure,                                                                                                                                                    
(gdb) up
#3  0x00007ffff6f093d6 in signal_emit_unlocked_R.isra.0 (node=node@entry=0x5555559a0cc0, detail=detail@entry=2335, instance=instance@entry=0x555556250c90, 
    emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fffffffcb80) at ../../../gobject/gsignal.c:3812
Downloading source file /usr/src/glib2.0-2.76.3-1ubuntu1/debian/build/deb/../../../gobject/gsignal.c
3812                  g_closure_invoke (handler->closure,                                                                                                                          
(gdb) up
#4  0x00007ffff6ef969a in g_signal_emit_valist (instance=<optimized out>, signal_id=<optimized out>, detail=<optimized out>, var_args=var_args@entry=0x7fffffffcd40)
    at ../../../gobject/gsignal.c:3565
3565        signal_emit_unlocked_R (node, detail, instance, NULL, instance_and_params);                                                                                            
(gdb) up
#5  0x00007ffff6ef9923 in g_signal_emit (instance=<optimized out>, signal_id=<optimized out>, detail=<optimized out>) at ../../../gobject/gsignal.c:3622
3622      g_signal_emit_valist (instance, signal_id, detail, var_args);
(gdb) up
#6  0x00007ffff6ee6dc4 in g_object_dispatch_properties_changed (object=0x555556250c90, n_pspecs=<optimized out>, pspecs=<optimized out>) at ../../../gobject/gobject.c:1428
1428        g_signal_emit (object, gobject_signals[NOTIFY], g_param_spec_get_name_quark (pspecs[i]), pspecs[i]);
(gdb) 
#7  0x00007ffff58ed458 in gst_object_dispatch_properties_changed (object=0x555556250c90, n_pspecs=1, pspecs=0x7fffffffceb0) at ../gst/gstobject.c:455
455       ((GObjectClass *)                                                                                                                                                        
(gdb) 
#8  0x00007ffff6edc5bc in g_object_notify_queue_thaw (object=0x555556250c90, nqueue=<optimized out>) at ../../../gobject/gobject.c:359
359         G_OBJECT_GET_CLASS (object)->dispatch_properties_changed (object, n_pspecs, pspecs);                                                                                   
(gdb) 
#9  0x00007ffff6eeea2c in g_object_set_valist (object=0x555556250c90, first_property_name=<optimized out>, var_args=0x7fffffffd040) at ../../../gobject/gobject.c:2793
2793        g_object_notify_queue_thaw (object, nqueue);
(gdb) 
#10 0x00007ffff6eeeed4 in g_object_set (_object=0x555556250c90, first_property_name=first_property_name@entry=0x7fffd80c6901 "zoom") at ../../../gobject/gobject.c:2957
2957      g_object_set_valist (object, first_property_name, var_args);
(gdb) 
#11 0x00007fffd80c2882 in gst_camera_bin_create_elements (camera=0x555556ca33f0) at ../gst/camerabin2/gstcamerabin2.c:1742
Downloading source file /usr/src/gst-plugins-good1.0-1.22.3-1ubuntu1/obj-x86_64-linux-gnu/../gst/camerabin2/gstcamerabin2.c
[###                                                                                                                                                                            ]
warning: Source file is more recent than executable.                                                                                                                               

1742        g_object_set (camera->src, "zoom", camera->zoom, NULL);
(gdb) 
#12 gst_camera_bin_change_state (element=0x555556ca33f0, trans=GST_STATE_CHANGE_NULL_TO_READY) at ../gst/camerabin2/gstcamerabin2.c:1891
1891          if (!gst_camera_bin_create_elements (camera)) {
(gdb) 
#13 0x00007ffff591b801 in gst_element_change_state (element=element@entry=0x555556ca33f0, transition=transition@entry=GST_STATE_CHANGE_NULL_TO_READY) at ../gst/gstelement.c:3093
3093        ret = (oclass->change_state) (element, transition);                                                                                                                    
(gdb) 
#14 0x00007ffff591be37 in gst_element_set_state_func (element=0x555556ca33f0, state=GST_STATE_READY) at ../gst/gstelement.c:3047
3047      ret = gst_element_change_state (element, transition);
(gdb) 


#15 0x000055555556baf0 in WebcamControl::playDevice (this=0x7fffffffd730, device=0x555555df1a70) at /usr/include/x86_64-linux-gnu/qt5/QtCore/qscopedpointer.h:138
138         T *data() const noexcept
(gdb) 
#16 0x000055555556cd88 in WebcamControl::onBusMessage (message=<optimized out>, this=<optimized out>) at /usr/src/kamoso-23.04.2-0ubuntu1/src/video/webcamcontrol.cpp:308
308                 play();                                                                                                                                                        
(gdb) 
#17 webcamWatch (message=<optimized out>, user_data=0x7fffffffd730) at /usr/src/kamoso-23.04.2-0ubuntu1/src/video/webcamcontrol.cpp:244
244         wc->onBusMessage(message);
(gdb) 
#18 0x00007ffff590584f in gst_bus_source_dispatch (source=0x555556334b90, callback=0x55555556cc20 <webcamWatch(GstBus*, GstMessage*, gpointer)>, user_data=0x7fffffffd730)
    at ../gst/gstbus.c:821
821       keep = handler (bus, message, user_data);                                                                                                                                
(gdb) 
#19 0x00007ffff57c032f in g_main_dispatch (context=0x7fffec000ee0) at ../../../glib/gmain.c:3460
3460              need_destroy = !(* dispatch) (source, callback, user_data);                                                                                                      
(gdb) 
#20 g_main_context_dispatch (context=0x7fffec000ee0) at ../../../glib/gmain.c:4200
4200          g_main_dispatch (context);
(gdb) 
#21 0x00007ffff581b148 in g_main_context_iterate.constprop.0 (context=0x7fffec000ee0, block=<optimized out>, dispatch=1, self=<optimized out>) at ../../../glib/gmain.c:4276
4276        g_main_context_dispatch (context);                                                                                                                                     
(gdb) 
#22 0x00007ffff57bf170 in g_main_context_iteration (context=0x7fffec000ee0, may_block=1) at ../../../glib/gmain.c:4343
4343      retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF);
(gdb) 
#23 0x00007ffff5d150ea in QEventDispatcherGlib::processEvents (this=0x555555669db0, flags=...) at kernel/qeventdispatcher_glib.cpp:423
423         bool result = g_main_context_iteration(d->mainContext, canWait);                                                                                                       
(gdb) 
#24 0x00007ffff5cb99db in QEventLoop::exec (this=this@entry=0x7fffffffd540, flags=..., flags@entry=...) at ../../include/QtCore/../../src/corelib/global/qflags.h:69
Downloading source file /usr/src/qtbase-opensource-src-5.15.9+dfsg-3/src/corelib/../../include/QtCore/../../src/corelib/global/qflags.h
[###                                                                                                                                                                            ]


69          Q_DECL_CONSTEXPR inline operator uint() const noexcept { return uint(i); }                                                                                             
(gdb) 
#25 0x00007ffff5cc1e2a in QCoreApplication::exec () at ../../include/QtCore/../../src/corelib/global/qflags.h:121
121         Q_DECL_CONSTEXPR inline QFlags(Enum flags) noexcept : i(Int(flags)) {}                                                                                                 
(gdb) 
#26 0x00007ffff6135df0 in QGuiApplication::exec () at kernel/qguiapplication.cpp:1863
Downloading source file /usr/src/qtbase-opensource-src-5.15.9+dfsg-3/src/gui/kernel/qguiapplication.cpp
[ ###                                                                                                                                                                           ]
warning: Source file is more recent than executable.                                                                                                                               
1863        return QCoreApplication::exec();
(gdb) 
#27 0x00007ffff696bf09 in QApplication::exec () at kernel/qapplication.cpp:2832
Downloading source file /usr/src/qtbase-opensource-src-5.15.9+dfsg-3/src/widgets/kernel/qapplication.cpp
2832        return QGuiApplication::exec();                                                                                                                                        
(gdb) 
#28 0x0000555555567585 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/kamoso-23.04.2-0ubuntu1/src/main.cpp:47
Downloading source file /usr/src/kamoso-23.04.2-0ubuntu1/src/main.cpp
47          return app.exec();                                                                                                                                                     
(gdb) 
Initial frame selected; you cannot go up.
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