As soon as WPML is installed and activated, the following error occurs.

PHP Fatal error: Uncaught Error: Cannot use object of type Closure as array in /wp-content/plugins/debugpress/core/track/Tracker.php:694

The following bugfix would provide a remedy:

if ( !is_array($call['args']) || !is_array($call['args'][0]) ) {
    continue;
}

This must be inserted above (Tracker.php line 694)

if ( isset( $call['args'][0][0] ) && $call['args'][0][0] instanceof Tracker )

Maybe it would be possible to integrate this bugfix in the next update.