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My recommendation, after years of experience upgrading Macs, is that you use CleanMyMac X. Likewise, it’s always a good idea to clear out the clutter before you upgrade. As you can imagine, upgrading your operating system on a junk-filled Mac is rather like putting one layer of wallpaper on top of another - eventually you have to scrape it off and start again. And as you upgrade year after year, you accumulate more and more.
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That means that all the system junk your Mac has accumulated over the years stays there. When you do a regular upgrade, the installer replaces some files on your Mac with others, but leaves most untouched. If your Mac still runs Mojave or an even older macOS version, you'll be amazed by all the new features and improvements in Catalina. So here’s how to upgrade to macOS Catalina. MacOS Catalina was the newest operating system by Apple until macOS Big Sur succeeded it in 2020.
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