I do it mainly to find failures. I'm not sure if it's required, my gut says no, but I'm not sure on that... it's a good question.
One of the best ways to do a burn in is to create a sequence and command all lights green, hold for a while, then red, then blue, then white, then do some fading in and out, then some twinkle/shimmer, etc. Then play and repeat. You could also add an effect and click on it and have it play, then wait a while and change. Just know that full white things will get hot, this will check your ventilation, or lack thereof.
I did my burn in for 6 hours. I've heard others go for 24-48 hours.
I had 3 pixels fail during burn in and 1 fail afterwards (but it's possible I missed that one during burn in).
James
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