Thanks for the additional information. Still it is a bug in Spyder, not in Qt:
1) Cleanlooks and Plastique styles are inheriting from QProxyStyle. 2) So in Spyder’s HTMLDelegate.paint method, options.widget.style() returns a QProxyStyle. 3) In QProxyStyle.subElementRect method, the third argument is not optional, so should be specified: https://doc.qt.io/qt-5/qproxystyle.html#subElementRect In C++, if the two-argument call is used, the compiler would ignore QProxyStyle::subElementRect and fall back to QCommonStyle::subElementRect. However, in Python there is no concept of overloading methods so this is not possible. So Qt and PyQt behave according to their documentation. Replacing style.subElementRect(QStyle.SE_ItemViewItemText, options) with style.subElementRect(QStyle.SE_ItemViewItemText, options, None) in Spyder code seems to help. With regards to crash when using GTK2, it is a different and known issue. Qt uses GTK3 platformtheme (i.e. dialogs) by default, and it is incompatible with GTK2. If you want to use GTK2 then you should export QT_QPA_PLATFORMTHEME=gtk2. But I recommend against using GTK2 as it is deprecated. ** Changed in: qtstyleplugins-src (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1832019 Title: Error when going to 'Tools -> Preferences -> Keyboard shortcuts' in Spyder3 in Bionic To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pyqt5/+bug/1832019/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
