What is a DFU mode on an iPod Touch?
What is a DFU mode?
[Re-Titled by Moderator]
iPod Touch (3rd Gen)
It stands for Device Firmware Update. See If you can't update or restore your iPhone or iPod touch - Apple Support. It is similar to the recovery mode mentioned there but the display should remain blank. See https://www.imore.com/how-to-iphone-ipad-dfu-mode.
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