I found a little, not really disturbing bug, which occurs if click on any of the buttons or elements in the right upper corner of 1Password.
As shown in the picture, the menu appears on the main/middle screen (3 monitors, 1P opened on the left one) and not where the mouse is located.
If I click a little bit to the left, where nothing is it appears in the right place:
Up to this, the 7.3 beta works like a charm!
1Password Version: 7.3.602
Extension Version: 18.104.22.168
OS Version: Windows 10 1803 17134.407
Sync Type: Dropbox