I installed OpenCore Legacy Patcher on my ancient MacBook. Updates to MacOS from Apple for that system had stopped some time ago and they were just doing the occasional security patch.
I’d read about OpenCore before and thought it sounded interesting but until I got my new MacBook, I was a little hesitant to use it on something that was a daily driver.
The installation process was as documented and went fairly smoothly. I used a USB-C dock that has a Micro SD slot to use for the macOS installer that you need to build as part of the process. The entire process took an hour or so.
I’ve encountered a few weird issues after the upgrade. First, the Finder crashed anytime I Ctrl-clicked on something. That’s a bit of a problem, but went away after letting the sync with iCloud finish and rebooting the machine. I also ran into a problem when I tried to run git. Although the Xcode tools were installed, they couldn’t be found (maybe because they were the ones form the old MacOS?). Anyway, I ran
sudo rm -rf /Library/Developer/CommandLineTools
sudo xcode-select --install
and everything is working fine now.
So far, it’s been a great experience. I’m not going to say everything is snappy on a nine year old system, but it’s nice that it works at all. It will now become an alternate system that is up to date and ready to go.