Recommended
EEVblog #388 - Fake Apple USB Charger Teardown
Why people recommend it
Dave Jones tears down a counterfeit Apple USB charger and shows its poor mains isolation; cited in discussions of cheap chargers and the shock risk they carry.
In their words
Seriously some of these things are scary.
BB ON on electronics.stackexchange.com, Jun 2014. CC BY-SA.
If you want to see what kind of low-quality chargers are sold, this EEVBlog video of a fake Apple charger disassembling is interesting!
LorenzoDonati4Ukraine-OnStrike on electronics.stackexchange.com, Jun 2015. CC BY-SA.
Beware though, that this is VERY fertile ground for counterfeiters and other dodgy operations, so stick to the more reputable suppliers for this!
AaronD on electronics.stackexchange.com, Jan 2022. CC BY-SA.