Took me 9 hours to make a CSS-only coffee cup because of ONE shadow bug
I spent 9 hours on a coffee cup made from a single div and 3 pseudo-elements, all because Safari kept clipping my box-shadow on the handle. Turns out a tiny blur radius of 0.5px fixed it, so what tiny browser quirk ate your whole weekend?
Man, Safari's shadow rendering has burned me too, especially on rounded corners where it just gives up. Try adding a tiny transparent outline or a second stacked shadow, that usually tricks it into behaving.