Tesla's newest Easter Egg popped up over this past weekend when software update 188.8.131.52.17 was applied.
This update apparently fixes/changes some Summon mode features, though we've yet to hear exactly what's been tweaked.
However, the Easter Egg temporarily brings about a rainbow "cowbell" road in Autopilot mode (demonstrated in video above by Bjorn Nylund).
Activation is simple. All you need to do is to activate autopilot then pull back on the autopilot stalk 4 times rapidly. Ride the rainbow!
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