Does flickering still happens? If flickering does not happen, restart your Mac regularly (without pressing any keys).
Apple logo will appear (do not release the Shift key yet) Start your Mac and immediately, press and hold the Shift key.You can use safe mode to identify your issue. On your Mac, go to System Preferences > Energy Saver > and uncheck the option for “Automatic graphics switching” (note that Mac Air models do not have this option, Mac Book Pro models have this option).Start your Mac, and immediately press the Option, Command, P, and R keys together for several seconds (around 20 seconds).Different Mac models require different steps to do this. Reset the System Management Controller (SMC).You can do so by opening the App Store on your Mac. Restart your Mac by going Apple menu >Restart.Please try each step until you resolve your problem: Here is what you can do if your Mac screen is flashing or flickering: Screen flickering issue, fixes Mac screen flickering can be caused by different issues. It further seems that some screen flickering issues are so severe that it makes it almost impossible to look at the screen. It seems that both retina and non-retina screens may experience this. Some users have started that the problem would occur randomly. Several MacBook users have reported that their screen displays are flickering.
