Re: U2518D, firmware M2T103, stuck
First, what specific monitor issue are you trying to correct by installing a monitor firmware?
You should not install a monitor firmware just because it is newer. Notice the Firmware Update description states, "Importance: Optional".
If stuck, all you can do is try to cancel out of it. If it bricks it, get an exchange.
No, you cannot backflash to an older version.
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