MediaStyleDropdownDefinition

The definition of a split-button dropdown that groups several media style buttons.

Integrators can declare custom dropdowns inline in config.mediaEmbed.toolbar alongside button-name strings; defaultItem is the discriminator that distinguishes a split-button media style dropdown from a generic toolbar grouping.

mediaEmbed: {
	toolbar: [
		'mediaEmbed:alignCenter',
		{
			name: 'mediaEmbed:myAlignments',
			title: 'Alignment',
			items: [ 'mediaEmbed:alignBlockLeft', 'mediaEmbed:alignBlockRight' ],
			defaultItem: 'mediaEmbed:alignBlockLeft'
		}
	]
}

All names (name, items[], defaultItem) use the full prefixed component-factory form. Items referencing styles that are not in the resolved config.mediaEmbed.styles list are filtered out at registration time. A dropdown that ends up with fewer than two items is skipped. If the configured defaultItem was filtered out, the first surviving item is used.