We have tried Firefox, Edge and Chrome Canary with same symptoms, updating all drivers, BIOS, re installation of the OS and still issues are occurring. We originally thought the issues were graphics related, but they seem to only be happening when in Google Calendar. Seems like an OS bug?
We have also turns hardware acceleration off in the browsers.
I have included some screenshots as well. The black bars at the top began in Firefox on Google Calendar and have penetrated other windows that have been placed on top (Acrobat in this example).
We are using an Intel NUC and a Laptop.