Fix of #3775 - wrong background color in ErrorDialog on macOS Sierra
Fix of #3775 - wrong background color in ErrorDialog on macOS Sierra

prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r,prusa3d/Slic3r