With the latest Qt 6.10 update, some programs have started crashing when using the environment variable QT_IM_MODULE=fcitx, such as Telegram and Featherpad.
The issue with Telegram has already been fixed, but as for Featherpad, according to the developer, the problem lies in /usr/lib/qt6/plugins/platforminputcontexts/libfcitx5platforminputcontextplugin.so.
Currently, the workaround is to launch the program using QT_IM_MODULE=ibus IBUS_USE_PORTAL=1.