Array to string conversion in execute-cache.php:1039 (breeze_commented_posts)

Hello,

We see this warning in the PHP error log of a site running Breeze 2.6.1 (it was the same on 2.6.0):

PHP Warning:  Array to string conversion in .../wp-content/plugins/breeze/inc/cache/execute-cache.php on line 1039

Cause: Breeze_Execute_Cache::get_wp_logged_in_cookie_value() loops over every cookie and casts the value to a string before checking the cookie name:

foreach ( $_COOKIE as $cookie_name => $cookie_value ) {
    $cookie_name  = (string) $cookie_name;
    $cookie_value = (string) $cookie_value;   // line 1039
    // the wordpress_logged_in_ name check comes only after this

Breeze itself sets the cookie breeze_commented_posts[<post_id>] for visitors who left a comment (inc/cache/purge-cache.php, line 174), and reads it back as an array in execute-cache.php (line 977). PHP parses a cookie name with square brackets into an array, so $_COOKIE['breeze_commented_posts'] is an array, and the cast on line 1039 raises the warning when such a visitor opens a page.

Steps to reproduce:

1. Enable page cache in Breeze.
2. Leave a comment as a guest on any post, so the browser gets breeze_commented_posts[123].
3. Open any page: the warning appears in the PHP error log.

Suggested fix: skip non-string values before the cast, or check the name first, for example:

foreach ( $_COOKIE as $cookie_name => $cookie_value ) {
    if ( ! is_string( $cookie_value ) ) {
        continue;
    }
    $cookie_name = (string) $cookie_name;

The value of such a cookie can never be a wordpress_logged_in_ cookie anyway, so skipping it does not change the behaviour of the check.

Thank you.