What is the problem?
The Tracker mini draws power from devices it is connected to. My iPhone complains about that (though it works), and other battery-powered devices are also being drained. It has its own battery though, so doesn’t need to draw power all the time.
What should this feature achieve?
Some devices (like Oxi One) have a mode where they don’t charge from the USB port while turned on. They still charge while turned off, so this doesn’t interfere with the ability to charge the Tracker when needed.
Are there any workarounds?
There are cables that cut the ground line, but they might introduce other problems. They’re also another thing to keep track of, when a regular cable could work with an appropriate setting in the firmware.
Any links to related discussions?
None that I’ve seen
Any references to other products?
This is from the Oxi One manual (the highlighted section specifically, I’m not asking for host mode in this wish 
):
