generate_default_color_palettes

This filter allows you to set the default color palettes inside your color pickers in the Customizer.

This filter requires an array in the return.

You should return 8 colors.

add_filter( 'generate_default_color_palettes', 'tu_custom_color_palettes' );
function tu_custom_color_palettes( $palettes ) {
	$palettes = array(
		'#000000',
		'#FFFFFF',
		'#F1C40F',
		'#E74C3C',
		'#1ABC9C',
		'#1e72bd',
		'#8E44AD',
		'#00CC77',
	);
	
	return $palettes;
}