It’s logical operator. You can learn about them here
It’s one of the basics, so if you are really interested in programming i recommend you to check this topic.
In my code if (query.items.length) returns true when array is not empty, and if (!query.items.length) returns true when it is empty.
Andrii unfortunely it’s working always at half. All works BUT the response on r-page is always “no user found” . IR-page is not able to show the message: ‘Email confirmed’