DocumentOutlineTableOfContentsConfig

An ordered array of model heading element names to include in the table of contents.

When set, only headings matching these names are rendered in the ToC widget, independently of documentOutline.headings.

The index of the heading in the array reflects the heading nesting level in the table of contents.

ClassicEditor
	.create( {
		plugins: [ TableOfContents, /* ... */ ],
		tableOfContents: {
			headings: [ 'heading1', 'heading2' ]
		}
	} )
	.then( /* ... */ )
	.catch( /* ... */ );

When not set, the ToC inherits headings from DocumentOutlineUtils (the existing default behavior).