Catalina
How to get macOS Catalina installed in an old Mac
macOS Catalina Patcher is an application that lets you install and run macOS 10.15 on unsupported hardware.
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Apple releases MacOS Catalina 10.15.3 Beta 3 for testing
MacOS Catalina 10.15.3 beta 3 is out for testing and it may focus primarily on bug fixes, enhancements, and small improvements to MacOS Catalina, according to OSXDaily.
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