When trying to root my OnePlus3 I ran into the issue that when running
fastboot devices my output is blank. Some people said that even while it returns a blank output other commands should still work but
fastboot oem unlock just says it's waiting for my device without ever proceeding. Also in my device manager I can see ´Kedacom USB device > Android Bootloader Interface´ and I think that might be the problem which I also found in "Kedacom USB Device doesnt work with fastboot Nexus 5x". However no solution is provided here.
When I'm using
adb devices after a normal boot it returns
List of devices attached
2a04cf0c device and in my device manager I can also see
USB devices > ADB interface