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Intel-based Macs: Built-in display dims before sleep
Issue or symptom
The screen may dim before sleep on an Intel-based Mac's built-in display, even if the Energy Saver setting "Automatically reduce the brightness of the display before display sleep" is disabled. This setting may no longer be in effect after restarting the computer.
Products affected
Intel-based Mac with built-in display (MacBook, MacBook Pro)
Solution
As a workaround, to temporarily stop the display from dimming before display sleep, enable the Energy Saver preferences setting "Automatically reduce the brightness of the display before display sleep," then disable it again.
You may also be able to temporarily avoid the issue by putting the computer to sleep and waking it.
Note: The issue will return each time the computer is restarted.
This document will be updated as more information becomes available.