The patch is known as DosDude Catalina Patcher.
CCLEANER FOR MAC OS SIERRA FREE DOWNLOAD INSTALL
There's a patch that lets you install Catalina to Macs that are not officially supported. If the year is the same or above the previous compatibility list, then you should be able to install macOS Catalina formally. In the Overview tab, look at the Mac model year below the OS version number. If you're unsure what version of macOS you have, you can check your macOS or OS X version by clicking the Apple icon at the top-left corner of Mac's screen, then select About This Mac. This means that if you have a Macbook Air or iMac released in 2011, you won't be able to upgrade your OS to Catalina.
This can be obtained from the Mac App Store using a machine that supports Mojave, or by using the built-in downloading feature of the tool. A copy of the macOS Mojave Installer App.
CCLEANER FOR MAC OS SIERRA FREE DOWNLOAD HOW TO
In this guide, we'll walk you through how to use the tool to install macOS 10.12 Sierra on older Mac hardware, which claims not to. In many cases this turned out to be true, and with a few tweaks and amendments many of the 'unsupported' machines have been brought back into the fold by a tool by dosdude1, called macOS Sierra Patcher. Definitely not 'dubious' third party software imho. He is a meticulous programmer who offers excellent support for the tool, and also a respected contributor on the Low End Mac facebook page. Regarding the download of the full macOS High Sierra installer app – I have personally used dosdude1's patcher version for Sierra many times.