Steam Dropping Support for OS X 10.10 Yosemite and Earlier - MacRumors

Steam recently announced that it will stop supporting macOS versions 10.7 ("Lion"), 10.8 ("Mountain Lion"), 10.9

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Valve Dropping Steam Support on Old macOS Versions

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OS X El Capitan on Unsupported Macs

Steam to end support for macOS El Capitan and Sierra in September

Apple Releases OS X Yosemite 10.10.3 With Photos for OS X App

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Popular Drag-and-Drop Mac App 'Yoink' Gains Configurable Clipboard

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