[Question] Trusted domain error


My Nextcloud log file has full of warning messages like below. The intruding domains are from all over the world. I believe these are just warnings as stated but Nextcloud is well protected. Is there anything I need to worry about the security of my Nextcloud? Thank you.

App	Message	Time
Warning	core	Trusted domain error. "" tried to access using "My domain" as host.	2017-05-07T04:03:51-0400

No, nothing to worry about, just robots or people who try to findout if your server has attackpoints…
…but it hasn’t (I hope).

Thank you Soko. I just wanted to be sure. They are scary!