After upgrading to Neon 5.7 PureRef app font became so tiny that it's hardly possible to read. If I start the app in terminal, it says
"Cannot find font directory /usr/local/Qt-5.6.0/lib/fonts - is Qt installed correctly?
libpng warning: iCCP: known incorrect sRGB profile
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainFrame::setMaximized(bool)
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainFrame::setAlwaysOnTop(bool)
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainFrame::setAlwaysOnBottom(bool)
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainWindow::setMouseTransparent(bool)
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainWindow::setOverlay(bool)
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainWindow::setWindowLocked(bool)
QObject::connect: Incompatible sender/receiver arguments
        Action::triggered(int) --> MainWindow::setCanvasLocked(bool)
"
If I start the app as root, the font gets readable. 
What shall I do?