Just upgraded from Android Studio 4.1 to ArcticFox 2020.3.1.
Emulator was working fine in 4.1 but now nothing shows. Sometimes the status line says 'waiting for emulator to start...' for a few seconds, but otherwise nothing, no error messages. As part of the upgrade, it recommended to use the HAXM accelerator which I installed. I have checked this thread but it hasn't helped (it refers to a much older version of Studio). The app runs OK on a real device.
I have tried adding a new (different) virtual device; same problem. I also have the same problem on two upgraded PCs (Windows 10)