Difference between - desktop and desktop?

Your software
mautic 3.1.1-rc
php 7.3.22

Your problem
I added the widget Devices for email to the dashboard and it shows me 2x desktop. So what’s the difference? I was actually only using my one and only desktop, maybe different IPs via a VPN. But how can there be 2 types of desktop?

Screenshot 2020-09-22 at 18.49.49

My guess is, I was using Safari 4x and Firefox 36x