Strange outgoing connection

Somebody help please.
Why my mikrotik generate this strange connections? Does somebody have any idea? What can i do?
What is this? There is many of this connections.
Source address are PC from my domain. When i go to this pc i can’t see nothing strange.
10days ago my mikrotik was affected with some botnet vulnerability.
Thank you in advantage.
mikrotik.jpg

Simple Google search for https://ipinfo.io/216.58.205.99 shows that it is Google IP so I suspect that that it is a connection to Gmail or Google lookup from web browser.
You have session timeout set to 24 h. so if browser opens connection to google.com and then you change web page, the connection to Google’s farm is still open. Try to close browsers or e-mail programs and look what will happen.
You can also change session timeout to lower times … press Tracking button and look for TCP settings. I use 3 hours without any problems on many routers.

Thank you verry much for your reply and clarification.
Cheers.