Comment # 4 on bug 937995 from Ladislav Slezak

Um, the backtrace points to libQt5:

/usr/lib64/liby2.so.4(signal_log_backtrace()+0x18)[0x7f2583dab228]
/usr/lib64/liby2.so.4(signal_handler(int)+0x149)[0x7f2583dab419]
/lib64/libc.so.6(+0x336c0)[0x7f25820896c0]
/usr/lib64/libQt5Gui.so.5(QFont::QFont(QFont const&)+0xb)[0x7f257e23727b]
/usr/lib64/libQt5Gui.so.5(+0x1d99f5)[0x7f257e28b9f5]
/usr/lib64/libQt5Gui.so.5(QTextFormat::clearProperty(int)+0x1e)[0x7f257e28723e]
/usr/lib64/libQt5Gui.so.5(QTextCursorPrivate::setCharFormat(QTextCharFormat
const&, QTextDocumentPrivate::FormatChangeMode)+0x39)[0x7f257e2ca699]
/usr/lib64/libQt5Widgets.so.5(+0x315873)[0x7f257eaee873]
/usr/lib64/libQt5Widgets.so.5(QTextEdit::setPlainText(QString
const&)+0x11)[0x7f257ead2a01]
/usr/lib64/yui/libyui-qt.so.6(YQLogView::displayLogText(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> > const&)+0x90)[0x7f257f6793e0]
/usr/lib64/libyui.so.6(YLogView::updateDisplay()+0x3c)[0x7f25803e3bdc]
/usr/lib64/libyui.so.6(YLogView::appendLines(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> > const&)+0x1e1)[0x7f25803e40a1]
/usr/lib64/libyui.so.6(YLogView::setProperty(std::__cxx11::basic_string<char,
std::char_traits<char>, std::allocator<char> > const&, YPropertyValue
const&)+0x243)[0x7f25803e4bb3]
/usr/lib64/YaST2/plugin/libpy2UI.so.2(YCP_UI::ChangeWidget(YCPValue const&,
YCPValue const&, YCPValue const&)+0x32e)[0x7f25806550be]
/usr/lib64/YaST2/plugin/libpy2UI.so.2(YUINamespace::ChangeWidget(YCPTerm
const&, YCPSymbol const&, YCPValue const&)+0x24)[0x7f258063e094]
/usr/lib64/YaST2/plugin/libpy2UI.so.2(YUIFunction::evaluateCall_int()+0x215a)[0x7f258064153a]