I am a Karabiner Elements user and had donated to it previously and even talked about some custom key mappings I use. Things had a been a bit spotty with it since macOS Big Sur but with the latest version 13.0 and macOS 11.0, 11.1, and 11.2 things were fine. However, yesterday I updated one of my Macs to 11.3 Beta and that broke Karabiner. In addition to it I noticed that my M1 Mac always reports that it restarted due to a kernel panic whenever I restart; and when I Googled for the panic report entries the first hit was Karabiner. Looks like things aren’t entirely with Karabiner and macOS Big Sur after all.