For everything in life there is a JetBrains product. Right? Right.
So for C# development when using Linux, I wanted to use JetBrains Rider.
All went well, I needed to upgrade to Ubuntu 21.04 to install dotnet, but surprisingly, that all went off without a hitch. No full OS reinstall needed! Miracles do happen. I should put on a lottery ticket.
Anyway, by and large my dotnet’ing then went well enough. At least for the stuff I was doing (tutorials and exercism exercises, mainly). But then one day (today, just now) I wanted to debug something, and when I tried I got the message:
Mono location is not specified in settings correctly and can not be discovered automatically. Please check Mono settings under File | Settings | Build, Execution, Deployment | Toolset and Build
Being a dotnet newb, I didn’t fully understand why / what Mono is. As best I recalled from some previous work with Unity, Mono was a kind of editor that worked cross platform? Is that even the same thing? Who the heck knows.
Anyway, after a few failed attempts at fixing this following anonymous folk on StackOverflow (copy > paste > run > curse!), I discovered the answer. Very simple. Bit of a face palm moment:
sudo apt install mono-devel
So, err, yeah. Won’t work if it’s not installed.