A burned out bulb.
I just checked and no bulb is burned out. Could it be the flasher module?
Just to verify, you should have 2 bulbs on each side of the rear flashing. 1 larger one on each side of the front and then a smaller on the front as well as a corner lens. If 1 of the 2 in the rear go out it will make it flash fast. If it's flashing fast on both left and right it would be worth changing the blinker relay/motor.
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