multisite clash between WP_DEBUG and media library grid view

I’m running a local bitnami installed wordpress multisite on a linux box. No plugins are active, the theme is twenty fifteen. The following problem occurs on both Firefox and Chrome: When WP_DEBUG is set to true, the grid view in the media library doesn’t work. The spinner keeps spinning. The list view works. When WP_DEBUG is set to false, the grid view works fine.

Any ideas what might be wrong?

Here is wp_config with passwords, keys, salt values removed:

<?php

define('WP_ALLOW_MULTISITE', true);
/**
*
* @package WordPress
*/

// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define('DB_NAME', 'bitnami_wordpress');

/** MySQL database username */
define('DB_USER', 'bn_wordpress');

/** MySQL database password */
define('DB_PASSWORD', '');

/** MySQL hostname */
define('DB_HOST', 'localhost:3306');

/** Database Charset to use in creating database tables. */
define('DB_CHARSET', 'utf8');

/** The Database Collate type. Don't change this if in doubt. */
define('DB_COLLATE', '');

/**#@+
* Authentication Unique Keys and Salts.
*
*
* @since 2.6.0
*/
define('AUTH_KEY', '');
define('SECURE_AUTH_KEY', '');
define('LOGGED_IN_KEY', '');
define('NONCE_KEY', '');
define('AUTH_SALT', '');
define('SECURE_AUTH_SALT', '');
define('LOGGED_IN_SALT', '');
define('NONCE_SALT', '');

/**#@-*/

/**
* WordPress Database Table prefix.
*/
$table_prefix = 'wp_';

/**
* For developers: WordPress debugging mode.
*
*/
define('WP_DEBUG', true);
define('SCRIPT_DEBUG', true);

define( 'MULTISITE', true );
define( 'SUBDOMAIN_INSTALL', true );
define( 'DOMAIN_CURRENT_SITE', 'stack.the' );
define( 'PATH_CURRENT_SITE', '/' );
define( 'SITE_ID_CURRENT_SITE', 1 );
define( 'BLOG_ID_CURRENT_SITE', 1 );
define('WP_TEMP_DIR', '/opt/wordpress-4.1.1-0/apps/wordpress/tmp');

/* That's all, stop editing! Happy blogging. */

/** Absolute path to the WordPress directory. */
if ( !defined('ABSPATH') )
define('ABSPATH', dirname(__FILE__) . '/');

/** Sets up WordPress vars and included files. */
define( 'SUNRISE', 'on' );
require_once(ABSPATH . 'wp-settings.php');

And here is .htaccess :


# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^wp-admin$ wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^(wp-(content|admin|includes).*) $1 [L]
RewriteRule ^(.*\.php)$ $1 [L]
RewriteRule . index.php [L]
</IfModule>

# END WordPress

Thanks.