I just noticed some similarities between the toy blaster and the new stormy blaster. I don't know if they are just coincidences.
Actually I thought it looked like General Grievous' blaster, especially the white Hasbro one.
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I wager that you are correct on what we see on the troopers right thigh, i believe it to be a magnetic holster.In the next shot, we get a good look at the right thigh: no holster but a strange greeblie - doesn't necessarily look like the blaster clips on, but maybe! Also can see a little of the front of the blaster in right front troopers hand...
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