  We found that ZTF J185139.81+171430.3 = ZTF18abnbzvx shows a very short
[0.00858995(3) d = 12.37 min] and large-amplitude (0.8 mag) coherent variations
using Public Data Release of Zwicky Transient Facility observations. The only
known object that shows similar very short period, large-amplitude and coherent
variations is the unique white dwarf pulsar AR Sco. The variations in ZTF
J185139.81+171430.3 may arise from the mechanism as in AR Sco and should
deserve attention.
