How to customize the options to show color palettes?

[federicomarcantognini]

How to customize select options with colour palettes, similar to this end result:

I have an array of objects with label 'div ..' and label 'color palette name'
Many thanks

[janosh]

See the color scale select on this site built with svelte-multiselect: https://matbench-discovery.materialsproject.org/data#--chemical-diversity. Here's the code for that.