Was it a "plain vanilla" Linux Mint installation from the downloaded .iso?
What did you learn? Did you encounter any issues, bugs, or problems? Were there any special driver requirements? Do you have any recommendations or suggestions for those who will follow in your footsteps? (Like me!)
Are all of the ports and interfaces working? I am curious to about Thunderbolt and external display interfaces in particular. I have an underutilized iMac 12,1 (2011, slightly older than yours) and your post got me thinking.
No hassles with the installation. Once completed went to driver install. It had picked up wireless and graphics which installed on the click of the button. Thunderbolt I am not sure. I have no knowledge of what it is used for. I guess come the day I might need it I will work it out then. Suggestions, just give it a go. I am more than happy with it. It is far better than having Catalina on it. Well for me anyhow.
Now Tim Cook is throwing another tantrum over an Apple user being smart enough to know how to jailbreak an iMac. Gee, maybe since the person OWNS the damn thing, you should let them do whatever they want with it. It's just a thought...
I can't find the specifics right now, but there was an iPhone before the Apple product. It was a VOIP device. I want to say it was from Cisco. It wouldn't have been Oracle, 'cause Ellison wouldn't have let that slide.