Comment # 16 on bug 1140184 from Wolfgang Bauer

(In reply to Stakanov Schufter from comment #15)
> Created attachment 810494 [details]
> falcon segfaults at exit new backtrace
> 
> with the new settings.

Well, that's a completely different crash now.

Could you please report it upstream at bugs.kde.org against Falkon please?
Thanks.

The relevant backtrace now seems to be:
#6  QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::data
(this=0x8) at ../../include/QtCore/../../src/corelib/tools/qscopedpointer.h:140
#7  qGetPtrHelper<QScopedPointer<QObjectData> > (p=...) at
../../include/QtCore/../../src/corelib/global/qglobal.h:999
#8  QObject::d_func (this=0x0) at kernel/qobject.h:121
#9  QMetaObject::activate (sender=sender@entry=0x0, signalOffset=3,
local_signal_index=local_signal_index@entry=3, argv=argv@entry=0x0) at
kernel/qobject.cpp:3639
#10 0x00007f30bd08ac07 in QMetaObject::activate (sender=sender@entry=0x0,
m=m@entry=0x7f30be313dc0 <History::staticMetaObject>,
local_signal_index=local_signal_index@entry=3, argv=argv@entry=0x0) at
kernel/qobject.cpp:3629
#11 0x00007f30bdfee8c3 in History::resetHistory (this=this@entry=0x0) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/build/src/lib/FalkonPrivate_autogen/ZGCQNSLDUB/moc_history.cpp:185
#12 0x00007f30bdee353f in History::clearHistory (this=0x0) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/src/lib/history/history.cpp:250
#13 0x00007f30bde88359 in MainApplication::saveSettings (this=0x7ffd858688a0)
at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/src/lib/app/mainapplication.cpp:781
#14 0x00007f30bdff6c2d in MainApplication::qt_static_metacall
(_o=0x7ffd858688a0, _c=<optimized out>, _id=<optimized out>, _a=<optimized
out>) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/build/src/lib/FalkonPrivate_autogen/VJIZ3MDCXP/moc_mainapplication.cpp:148
#15 0x00007f30bd08a535 in QMetaObject::activate (sender=0x7ffd858688a0,
signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=0,
argv=argv@entry=0x7ffd85868770) at kernel/qobject.cpp:3767
#16 0x00007f30bd08ac07 in QMetaObject::activate (sender=<optimized out>,
m=m@entry=0x7f30bd516640 <QCoreApplication::staticMetaObject>,
local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffd85868770)
at kernel/qobject.cpp:3629
#17 0x00007f30bd05a0e7 in QCoreApplication::aboutToQuit (this=<optimized out>,
_t1=...) at .moc/moc_qcoreapplication.cpp:249
#18 0x00007f30bd05e60b in QCoreApplicationPrivate::execCleanup
(this=0x556161beee70) at kernel/qcoreapplication.cpp:1317
#19 0x00007f30bd0629cd in QCoreApplication::exec () at
kernel/qcoreapplication.cpp:1301
#20 0x000055616003c856 in main (argc=<optimized out>, argv=0x7ffd85868a98) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/src/main/main.cpp:155
#6  QScopedPointer<QObjectData, QScopedPointerDeleter<QObjectData> >::data
(this=0x8) at ../../include/QtCore/../../src/corelib/tools/qscopedpointer.h:140
#7  qGetPtrHelper<QScopedPointer<QObjectData> > (p=...) at
../../include/QtCore/../../src/corelib/global/qglobal.h:999
#8  QObject::d_func (this=0x0) at kernel/qobject.h:121
#9  QMetaObject::activate (sender=sender@entry=0x0, signalOffset=3,
local_signal_index=local_signal_index@entry=3, argv=argv@entry=0x0) at
kernel/qobject.cpp:3639
#10 0x00007f30bd08ac07 in QMetaObject::activate (sender=sender@entry=0x0,
m=m@entry=0x7f30be313dc0 <History::staticMetaObject>,
local_signal_index=local_signal_index@entry=3, argv=argv@entry=0x0) at
kernel/qobject.cpp:3629
#11 0x00007f30bdfee8c3 in History::resetHistory (this=this@entry=0x0) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/build/src/lib/FalkonPrivate_autogen/ZGCQNSLDUB/moc_history.cpp:185
#12 0x00007f30bdee353f in History::clearHistory (this=0x0) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/src/lib/history/history.cpp:250
#13 0x00007f30bde88359 in MainApplication::saveSettings (this=0x7ffd858688a0)
at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/src/lib/app/mainapplication.cpp:781
#14 0x00007f30bdff6c2d in MainApplication::qt_static_metacall
(_o=0x7ffd858688a0, _c=<optimized out>, _id=<optimized out>, _a=<optimized
out>) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/build/src/lib/FalkonPrivate_autogen/VJIZ3MDCXP/moc_mainapplication.cpp:148
#15 0x00007f30bd08a535 in QMetaObject::activate (sender=0x7ffd858688a0,
signalOffset=<optimized out>, local_signal_index=local_signal_index@entry=0,
argv=argv@entry=0x7ffd85868770) at kernel/qobject.cpp:3767
#16 0x00007f30bd08ac07 in QMetaObject::activate (sender=<optimized out>,
m=m@entry=0x7f30bd516640 <QCoreApplication::staticMetaObject>,
local_signal_index=local_signal_index@entry=0, argv=argv@entry=0x7ffd85868770)
at kernel/qobject.cpp:3629
#17 0x00007f30bd05a0e7 in QCoreApplication::aboutToQuit (this=<optimized out>,
_t1=...) at .moc/moc_qcoreapplication.cpp:249
#18 0x00007f30bd05e60b in QCoreApplicationPrivate::execCleanup
(this=0x556161beee70) at kernel/qcoreapplication.cpp:1317
#19 0x00007f30bd0629cd in QCoreApplication::exec () at
kernel/qcoreapplication.cpp:1301
#20 0x000055616003c856 in main (argc=<optimized out>, argv=0x7ffd85868a98) at
/usr/src/debug/falkon-3.0.1-lp151.2.6.x86_64/src/main/main.cpp:155
(which you should add to that bug report)

I.e. it seems to crash now when saving the settings.

You could also try the latest Falkon 3.1.0 from the KDE:Extra repo to see if it
might have been fixed in this version.