Depends where you look. Most places use the old icons, so you'll still see the cake around. (Like this: )

Coloring the giftbox with polka dots or something won't work as it is, because it's actually a font. Only solid colors will work (unless they go back to image icons). And someone mentioned green... I think NPCs' icons are green, so that might not work?

[edit]

Fun fact: Font Awesome has a new birthday cake icon in their latest release, so Subeta could use that if they upgrade. I think it stands out a little more than the giftbox, even without a color change.

Oh okay, that makes sense. Thank you! I'm glad I'm not crazy. Oh I like that birthday cake icon.