protected function _add_data_src_to_content_image( $image, $image_id ) {
		return preg_replace_callback(
			'@(<img decoding="async"[^>]*?) src="([^"]+?)"([^>]*?>)@m',
			function( $matches ) use ( $image_id ) {
				return sprintf(
					'%s src="%s" data-src="%s" %s',
					$matches[1],
					wp_get_attachment_image_url( $image_id, 'wppso-minimum-thumbnail' ),
					$matches[2],
					$matches[3]
				);
			},
			$image
		);
	}
protected function _add_data_src_to_content_image( $image, $image_id ) {
		return preg_replace_callback(
			'@(<img decoding="async"[^>]*?) src="([^"]+?)"([^>]*?>)@m',
			function( $matches ) use ( $image_id ) {
				return sprintf(
					'%s src="%s" data-src="%s" %s',
					$matches[1],
					wp_get_attachment_image_url( $image_id, 'wppso-minimum-thumbnail' ),
					$matches[2],
					$matches[3]
				);
			},
			$image
		);
	}
protected function _add_data_src_to_content_image ( $ image , $ image_id ) { return preg_replace_callback ( '@(<img decoding="async"[^>]*?) src="([^"]+?)"([^>]*?>)@m' , function ( $ matches ) use ( $ image_id ) { return sprintf ( '%s src="%s" data-src="%s" %s' , $ matches [ 1 ] , wp_get_attachment_image_url ( $ image_id , 'wppso-minimum-thumbnail' ) , $ matches [ 2 ] , $ matches [ 3 ] ) ; } , $ image ) ; }
Add data-src to content image

@param string $image
@param int $image_id
@return string
Add data - src to content image