I have a subclassed NSBox. Inside I have some NSTextfields embedded, which show some strange artifacts in their corners (see image here). This is my subclass code for the NSBox:
    - (void)drawRect:(NSRect)rect {
    NSBezierPath* rectanglePath = [NSBezierPath bezierPathWithRoundedRect:rect
                                                                  xRadius: 4
                                                                  yRadius: 4];
    [NSColor whiteColor];
    [rectanglePath fill];
}
Any ideas? Thanks, Thomas