Telling them in advance will potentially make them more alert for problem coming from specific source. It will introduce bias.
The best they can do is notify the maintainers after they got the result for their research and give the maintainers an easy way to recover from vulnerability they intentionally create.
I never know about pdf inline animation. Do you have some sample of pdf files that contain inline animation? I would like to try them on various pdf viewer.
I don't think it is about higher torque. It is more about instant torque, which a characteristic of electric motors. AFAIK, they did not design the motor to behave that way, it just the natural behavior of the electric motor.
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