Fontawesome fonts do not work in Qml but do work in QWidgets

A lot of Font Awesome 5 font characters do not work with Qml but work with QWidgets. Maybe this is also related to QTBUG-61925?

Steps to reproduce:

1. Run the attached example.
2. Two widget ToolButtons are shown with correct symbols.
3. Two Qml ToolButtons are shown, one with the correct symbol, one with a wrong symbol.