generateClassNames(attributes) {...} registerBlockExtension( 'core/group', { extensionName: 'background-patterns', attributes: { hasBackgroundPattern: { type: 'boolean', default: false, }, backgroundPatternShape: { type: 'string', default: 'dots', }, backgroundPatternColor: { type: 'string', default: 'green' } }, classNameGenerator: generateClassNames, Edit: BlockEdit, } ); 47