I've had phones and chargers for over 2 decades. Never lost one due to this so my answer is doesn't matter or follow the maker's instructions.
Before charging my phone I always plug the charger in to the device, and then to the wall socket... I think that is correct, if not, please tell me.
And after charging an Smartphone, which end do you unplug first: the one that's connected in the device or the charger end?
Thanks.

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