the linear fit thing is very repeatable, so this is probably not necessary but here it is anyway:
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x0000000000000000
0x0000000000000000 in ?? ()
(gdb) where
#0 0x0000000000000000 in ?? ()
#1 0x0000000105a04130 in ?? ()
#2 0x000000010157b939 in QApplication::notify ()
#3 0x00000001000e8332 in pi::PixInsightApplication::notify ()
#4 0x00000001039795e6 in QCoreApplication::notifyInternal ()
#5 0x00000001015c3f3f in QWidgetPrivate::close_helper ()
#6 0x00000001015c40f4 in QWidget::close ()
#7 0x0000000100be7b75 in pi::WorkspaceWindow::Close ()
#8 0x0000000100c6fa02 in pi::WorkspaceWindow::qt_static_metacall ()
#9 0x000000010398e291 in QMetaObject::activate ()
#10 0x0000000100beada1 in pi::WorkspaceWindowTitleBarButton::mouseReleaseEvent ()
#11 0x00000001015c5db0 in QWidget::event ()
#12 0x000000010157b6b8 in QApplicationPrivate::notify_helper ()
#13 0x000000010157c008 in QApplication::notify ()
#14 0x00000001000e8332 in pi::PixInsightApplication::notify ()
#15 0x00000001039795e6 in QCoreApplication::notifyInternal ()
#16 0x0000000101583c28 in QApplicationPrivate::sendMouseEvent ()
#17 0x0000000101538301 in QMacCocoaAutoReleasePool::~QMacCocoaAutoReleasePool ()
#18 0x00007fff899a56d6 in -[NSWindow sendEvent:] ()
#19 0x000000010152fab2 in QString::clear ()
#20 0x00007fff899a1744 in -[NSApplication sendEvent:] ()
#21 0x00000001015333c2 in QString::clear ()
#22 0x00007fff898b72fa in -[NSApplication run] ()
#23 0x000000010153c5f0 in operator!= ()
#24 0x0000000103976a48 in QEventLoop::exec ()
#25 0x0000000103979d1b in QCoreApplication::exec ()
#26 0x00000001000fafbd in main ()
