I don't know how this happend but my Note8 is stuck on the OS downloading screen and it says do not turn off target. Holding the power button does not shut it down. Any suggestions?
Volume up + bixby button + power button for 10 seconds until it restarts, then reboot from recovery.
Disconnect charger cable first if you haven't already, it seems to make a difference on the N8 for some reason
Don't get paranoid about it happened unless it starts doing it several times a day, we all got stuck there sometime back in the root/Rom days when that was a must ??????