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USB-PD PSU almost thrown away because it would not charge a simple bicycle light
Sometimes manufacturers "do their own thing". Nintendo USB-C power supply can somehow power my soldering iron at 20V, but cannot charge a laptop.
Ran into the complement/opposite of this with a cheap handheld. It cannot be charged with a USB-C PD charger, but can be charged with a "dumb" USB-A to USB-C cord, all because the manufacturer cheaped out on 2 resistors.