Fix for display issue in FreeCAD-0.16 on GNOME in GNU/Linux.
If you have run FreeCAD-0.16 under GNOME you may have noticed that SpinBox controls (edit controls with associated up/down arrows) don’t show their content correctly.
FreeCAD, a Qt-based application, uses controls of this type with vertically placed up/down arrows while the default QT style used under GNOME (usually adwaita-qt4) places the up/down arrows side-by-side reducing the controls edit area.
A solution for this is to install the Qt4 Config utility and the Qt fusion style (on fedora use: dnf install qt-config qt4-style-fusion).
Simply start the Qt4 Config utility and under Appearance|Select GUI Style: choose fusion. Optionally, under Fonts|Family choose Cantarell and Fonts|Point Size: choose 11. Select File|Save and File|Exit to save the changes and exit Qt4 Config.
You will now find that Preference dialog and toolbar edit controls show their content correctly and the program text matches the rest of GNOME.