The padding of badge icons in achievements dropdown is off when viewing from mobile. Review pages aren't responsive yet (on mobile view, they look like a mix of full site/regular mobile view), but "even if the page isn't responsive, the padding between the items should be fine" (transcript).
Screenshot below, on Chrome 74.0, Android 5.1.1. No userscripts, or at least none that I willingly installed.
Apparently there's no repro on Catija's iPhone.