Multi Image Metabox

All output should be run through an escaping function (see the Security sections in the WordPress Developer Handbooks), found '$img'.

Missing $domain parameter in function call to __().

Detected usage of a non-sanitized input variable: $_POST[$k]

$_POST[$k] not unslashed before sanitization. Use wp_unslash() or similar

Detected usage of a possibly undefined superglobal array index: $_POST['post_ID']. Check that the array index exists before using it.

Resource version not set in call to wp_enqueue_script(). This means new versions of the script may not always be loaded due to browser caching.

In footer ($in_footer) is not set explicitly wp_enqueue_script; It is recommended to load scripts in the footer. Please set this value to `true` to load it in the footer, or explicitly `false` if it should be loaded in the header.

PHP file should prevent direct access. Add a check like: if ( ! defined( 'ABSPATH' ) ) exit;

Tested up to: 3.5 < 7.0. The "Tested up to" value in your plugin is not set to the current version of WordPress. This means your plugin will not show up in searches, as we require plugins to be compatible and documented as tested up to the most recent version of WordPress.

Missing "License" in Plugin Header. Please update your Plugin Header with a valid GPLv2 (or later) compatible license.

One or more tags were ignored. Please limit your plugin to 5 tags.

Incorrect Stable Tag. It's recommended not to use "Stable Tag: trunk". Your Stable Tag is meant to be the stable version of your plugin and it needs to be exactly the same with the Version in your main plugin file's header. Any mismatch can prevent users from downloading the correct plugin files from WordPress.org.