This update has various modernizations and a security fix for a vulnerability in the underlying Unity game engine.
The minimum system requirements have changed:
Windows 7 SP1+, x64 architecture
macOS High Sierra 10.13+, Apple Silicon or x64 architecture
Linux: Ubuntu 20.04, Ubuntu 18.04, and CentOS 7, x64 architecture
Version 1.2.2 is available on a beta branch for use with older computers that no longer meet the minimum system requirements.