Add Custom Attributes to Core Gutenberg Blocks. View full tutorials at https://jeffreycarandang.com/extending-gutenberg-core-blocks-with-custom-attributes-and-controls/

add-attributes.js

/**
 * WordPress Dependencies
 */
const { addFilter } = wp.hooks; 

/**
 * Add custom attribute for mobile visibility.
 *
 * @param {Object} settings Settings for the block.
 *
 * @return {Object} settings Modified settings.
 */
function addAttributes( settings ) {
	
	//check if object exists for old Gutenberg version compatibility
	if( typeof settings.attributes !== 'undefined' ){
	
		settings.attributes = Object.assign( settings.attributes, {
			visibleOnMobile:{ 
				type: 'boolean',
				default: true,
			}
		});
    
	}

	return settings;
}

addFilter(
	'blocks.registerBlockType',
	'editorskit/custom-attributes',
	addAttributes
);