If you’re adding theme support for editor-color-palette
then you need to add styles for those colours to your stylesheet. As documented:
Themes are responsible for creating the classes that apply the colors
in different contexts. Core blocks use “color” and “background-color”
contexts. So to correctly apply “strong magenta” to all contexts of
core blocks a theme should implement the following classes:.has-strong-magenta-background-color { background-color: #313131; } .has-strong-magenta-color { color: #f78da7; }
The class name is built appending ‘has-‘, followed by the class name
using kebab case and ending with the context name.