Show transparency of colors in preset colors

[MelanieW97]

Hello,

thanks for this great package!
There's just a tiny little thing which would be important to improve.
Users cannot see if a color in preset colors has got transparency or not. They just might look the same as a light color without transparency. Would it be possible to add a background image here, too - Just as you did with showing the picked color?

Preset color with transparency:

Preset color without transparency:

Maybe it'd even be possible to highlight the selected palette color with a border?

Thanks in advance. :)