macOS Mojave Patcher. Download and instructions available at: http://dosdude1.com/mojave pic.twitter.com/sPwdxAFBuf
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
Those are still there, but won't cause any performance issues. The system is still fully usable.
Most likely not, but it is still being worked on.
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