As I answered on that thread: yes and no No in the matter that it's a bug in clock app that makes it go grazy if it doesn't like your secondary font color. Yes in the matter if you changed the color with Theme Customizer and spotted one of these "not wanted" colors. So far I haven't found any logic of which colors causes this bug and since the clock app seems to be closed source, I can't look into it's source and maybe even provide patch for it