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Theine

Official Description

Theine costs less than a delicious cup of tea, but lasts forever.

Theine keeps your Mac awake. It prevents your Mac from falling asleep, dimming the screen or starting your screensaver. It adds a beautiful icon to your MenuBar and allows you to keep your OS awake infinitely or for a set time. It supports the OS X Yosemite Darkmode and looks just great on your retina-display.

Dear MacBook-Users: Theine is not working for security-reasons, when you close the lid.