Remove WPBakery elements from the builder.

gistfile1.txt

add_action( 'vc_after_init', function() {
    $elements = array(
        // Remove core wpbakery elements
        'vc_single_image',
        // Remove total elements
        'vcex_heading',
    );
    foreach ( $elements as $element ) {
        if ( function_exists( 'vc_remove_element' ) ) {
            vc_remove_element( $element );
        }
    }
} );