PHP Warnings

Hi There!

almost every day we get the following warnings at our php error logs:

[12-May-2021 01:43:10 UTC] PHP Warning:  Use of undefined constant DB_USER - assumed 'DB_USER' (this will throw an Error in a future version of PHP) in /kunden/customer_id/webseiten/hello-world.net/wordpress/wp-content/plugins/query-monitor/wp-content/db.php on line 140
[12-May-2021 01:43:10 UTC] PHP Warning:  Use of undefined constant DB_PASSWORD - assumed 'DB_PASSWORD' (this will throw an Error in a future version of PHP) in /kunden/customer_id/webseiten/hello-world.net/wordpress/wp-content/plugins/query-monitor/wp-content/db.php on line 140
[12-May-2021 01:43:10 UTC] PHP Warning:  Use of undefined constant DB_NAME - assumed 'DB_NAME' (this will throw an Error in a future version of PHP) in /kunden/customer_id/webseiten/hello-world.net/wordpress/wp-content/plugins/query-monitor/wp-content/db.php on line 140
[12-May-2021 01:43:10 UTC] PHP Warning:  Use of undefined constant DB_HOST - assumed 'DB_HOST' (this will throw an Error in a future version of PHP) in /kunden/customer_id/webseiten/hello-world.net/wordpress/wp-content/plugins/query-monitor/wp-content/db.php on line 140

Line 140 at db.php show the following entry:

// phpcs:ignore WordPress.WP.GlobalVariablesOverride.Prohibited
$wpdb = new QM_DB( DB_USER, DB_PASSWORD, DB_NAME, DB_HOST );

We are using:
Wordpress 5.7.1
PHP 7.4.15
QM 3.6.8

thnx for helping
Nick

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