Eh... We don't really have a set-in-stone rule, but I'm trying to keep the logical order: the most important or mandatory attributes first, similar or related attributes grouped together, etc. It's not perfect throughout the code, and I have a long distance goal to have a global pass over everything and fix the irregularities. Here, I put description after label because description logically comes after the label. That said, even this little piece has problems: it's unclear what `src` is -- it should be `icon`, with `iconsize` following it.