Personally: Linux desktop environments in general. Still couldn't figure out how to manually save session states since last upgrade (using Linux Mint Cinnamon

Personally: Linux desktop environments in general. Still couldn't figure out how to manually save session states since last upgrade (using Linux Mint Cinnamon now), took me a few hours to make hibernation work, and every time I upgrade, Korean IME is either broken, does something slightly differently, or first broken and after lengthy troubleshooting does something slightly differently. (After last upgrade, for some reason it's not working only on Facebook on Chrome. Fine, who needs to view Facebook on Linux anyway.) At work: saltstack - a machine provision framework that's trying hard to sound cute (pillar? grain? what the hell are they?) while making you write jinja templates which generate a yaml file while calling arbitrary python functions in a remote server, which is then sent to another remote server to be transformed into a sequence of commands in arbitrary order. Good luck debugging anything.