For what it's worth 3 years later, I'm running 12.3.1 on Fedora 34 (64-bit) right now.
I'd say it's fine, but I'm getting an occasional kernel crash while evaluating a notebook developed on my Windows license. The notebook imports an MS Excel file (*.xlsx) and creates several datasets with associations. I've got 32GB of RAM and no shortage of disk space either. I'm not sure what's causing the crash. (I just ran the whole thing again successfully while typing this. Can't troubleshoot it if it's behaving itself...)
