мая 26 10:28:33 work plasmashell[3560]: terminate called after throwing an instance of 'std::bad_alloc'
мая 26 10:28:33 work plasmashell[3560]:   what():  std::bad_alloc
мая 26 10:28:33 work plasmashell[3560]: KCrash: Application 'plasmashell' crashing... crashRecursionCounter = 2

happens every day multiple times. No any logs about it.

>мая 26 10:28:33 work plasmashell[3560]: terminate called after throwing an instance of 'std::bad_alloc'

ok, we need a backtrace to continue 
https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports#Retrieving_a_backtrace_with_GDB

Can you also see if memory usage increases before a crash?

Dear Bug Submitter,

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15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
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no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

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Also can you get a backtrace of what Plasma is doing when it's hung?

In a terminal window, run "gdb --pid `pidof plasmashell`"

And then at the prompt, type "bt"

May need to prefix the first command with sudo if it doesn't work

(In reply to Nate Graham from comment #5)
> Also can you get a backtrace of what Plasma is doing when it's hung?
> 
> In a terminal window, run "gdb --pid `pidof plasmashell`"
> 
> And then at the prompt, type "bt"

thanks, will try next time and will report here

Hi. I downloaded all debug symbols and here is backtrace of frozen plasmashell:

#0  0x0000777caeef04e9 in __futex_abstimed_wait_common64 (private=128, futex_word=0x777b8b400990, expected=2321895, op=265, abstime=0x0, cancel=true)
    at futex-internal.c:57
#1  __futex_abstimed_wait_common (futex_word=futex_word@entry=0x777b8b400990, expected=2321895, clockid=clockid@entry=0, abstime=abstime@entry=0x0,
    private=private@entry=128, cancel=cancel@entry=true) at futex-internal.c:87
#2  0x0000777caeef056f in __GI___futex_abstimed_wait_cancelable64 (futex_word=futex_word@entry=0x777b8b400990, expected=<optimized out>, clockid=clockid@entry=0,
    abstime=abstime@entry=0x0, private=private@entry=128) at futex-internal.c:139
#3  0x0000777caeef5bf3 in __pthread_clockjoin_ex (threadid=131372500911808, thread_return=0x0, clockid=0, abstime=0x0, block=<optimized out>)
    at pthread_join_common.c:102
#4  0x0000777c83440d1f in spa_thread_utils_join (retval=0x0, o=<optimized out>, thread=<optimized out>) at ../pipewire/spa/include/spa/support/thread.h:73
#5  pw_data_loop_stop (loop=0x59604ec0ea20) at ../pipewire/src/pipewire/data-loop.c:231
#6  0x0000777c834412a0 in pw_context_destroy (context=0x5960556b34e0) at ../pipewire/src/pipewire/context.c:425
#7  0x0000777c83e7c56f in PipeWireCore::~PipeWireCore (this=<optimized out>, this=<optimized out>) at /usr/src/debug/kpipewire/kpipewire-6.1.0/src/pipewirecore.cpp:75
#8  0x0000777c83e7c652 in PipeWireCore::~PipeWireCore (this=<optimized out>, this=<optimized out>) at /usr/src/debug/kpipewire/kpipewire-6.1.0/src/pipewirecore.cpp:81

#9  QtSharedPointer::CustomDeleter<PipeWireCore, QtSharedPointer::NormalDeleter>::execute (this=<optimized out>) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:161
#10 QtSharedPointer::ExternalRefCountWithCustomDeleter<PipeWireCore, QtSharedPointer::NormalDeleter>::deleter (self=<optimized out>)
    at /usr/include/qt6/QtCore/qsharedpointer_impl.h:179
#11 0x0000777c5fe4135c in QtSharedPointer::ExternalRefCountData::destroy (this=0x5960565d7610) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:115
#12 QSharedPointer<PipeWireCore>::deref (dd=0x5960565d7610) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:476
#13 QSharedPointer<PipeWireCore>::deref (dd=0x5960565d7610) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:472
#14 QSharedPointer<PipeWireCore>::deref (this=<synthetic pointer>) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:471
#15 QSharedPointer<PipeWireCore>::~QSharedPointer (this=<optimized out>, this=<optimized out>) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:284
#16 QSharedPointer<PipeWireCore>::clear (this=0x59604fb17ac8) at /usr/include/qt6/QtCore/qsharedpointer_impl.h:397
#17 MediaMonitor::connectToCore (this=0x59604fb17a90) at /usr/src/debug/kpipewire/kpipewire-6.1.0/src/monitors/mediamonitor.cpp:161
#18 0x0000777caf47a6f7 in QtPrivate::QSlotObjectBase::call (this=<optimized out>, r=<optimized out>, a=<optimized out>, this=<optimized out>, r=<optimized out>,
    a=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qobjectdefs_impl.h:469
#19 doActivate<false> (sender=<optimized out>, signal_index=<optimized out>, argv=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qobject.cpp:4086
#20 0x0000777caf482885 in QTimer::timeout (this=0x59604fb17b28, _t1=...) at /usr/src/debug/qt6-base/build/src/corelib/Core_autogen/include/moc_qtimer.cpp:224
#21 QTimer::timerEvent (e=<optimized out>, this=0x59604fb17b28) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qtimer.cpp:258
#22 QTimer::timerEvent (this=0x59604fb17b28, e=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qtimer.cpp:252
#23 0x0000777caf464fc9 in QObject::event (this=0x59604fb17b28, e=0x7ffd9d6ece10) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qobject.cpp:1427
#24 0x0000777cb12e551c in QApplicationPrivate::notify_helper (this=<optimized out>, receiver=0x59604fb17b28, e=0x7ffd9d6ece10)
    at /usr/src/debug/qt6-base/qtbase/src/widgets/kernel/qapplication.cpp:3287
#25 0x0000777caf41dd28 in QCoreApplication::notifyInternal2 (receiver=0x59604fb17b28, event=0x7ffd9d6ece10)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1142
#26 0x0000777caf59cc98 in QCoreApplication::sendEvent (receiver=<optimized out>, event=0x7ffd9d6ece10)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qcoreapplication.cpp:1583
#27 QTimerInfoList::activateTimers (this=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qtimerinfo_unix.cpp:434
#28 0x0000777caf67d979 in timerSourceDispatch (source=<optimized out>) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventdispatcher_glib.cpp:150
#29 0x0000777cadd85a89 in g_main_dispatch (context=0x777ca4000f00) at ../glib/glib/gmain.c:3344
#30 0x0000777cadde79b7 in g_main_context_dispatch_unlocked (context=0x777ca4000f00) at ../glib/glib/gmain.c:4152
#31 g_main_context_iterate_unlocked.isra.0 (context=context@entry=0x777ca4000f00, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>)
    at ../glib/glib/gmain.c:4217
#32 0x0000777cadd84f95 in g_main_context_iteration (context=0x777ca4000f00, may_block=1) at ../glib/glib/gmain.c:4282
#33 0x0000777caf67bcbd in QEventDispatcherGlib::processEvents (this=0x59604dd7b140, flags=...)
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventdispatcher_glib.cpp:394
    at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventdispatcher_glib.cpp:394
#34 0x0000777caf42801e in QEventLoop::processEvents (this=0x7ffd9d6ed0f0, flags=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventloop.cpp:100
#35 QEventLoop::exec (this=0x7ffd9d6ed0f0, flags=...) at /usr/src/debug/qt6-base/qtbase/src/corelib/kernel/qeventloop.cpp:182
#36 0x0000777caf42234d in QCoreApplication::exec () at /usr/src/debug/qt6-base/qtbase/src/corelib/global/qflags.h:74
#37 0x0000777cb12e13ba in QApplication::exec () at /usr/src/debug/qt6-base/qtbase/src/widgets/kernel/qapplication.cpp:2555
#38 0x000059604cfd4d66 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/plasma-workspace/plasma-workspace-6.1.0/shell/main.cpp:188

I see something about pipewire in backtrace. I am using pulseaudio, instead of pipewire, because pipewire sucks and sound is distorted.

Well, that's going to be at least part of the problem. PipeWire is required for thumbnails and screen recording to work. If you're forced it to not be present, you've got a system in an unsupported state.

are you sure, the root cause of hang is pipewire? I am not accessing thumbnails or use screenrecoring. It just hangs on idle.

The backtrace indicates it's doing something in PipeWire, and you've indicated that you have a custom unsupported PipeWire setup on the machine. Please consult distro resources or support channels to proceed. Thanks!