When I try to compile qucs in Debian/testing with Qt6, the command:
./configure --with-qt-name=Qt6
fails, and in the config.log I can find:
Package Qt6Script was not found in the pkg-config search path.
Perhaps you should add the directory containing `Qt6Script.pc'
to the PKG_CONFIG_PATH environment variable
Package 'Qt6Script', required by 'virtual:world', not found
According to the output of the apt-file search Qt6Script.pc, there is no package providing Qt6Script.