Ran into this on a MacBookPro M1 running Ventura. I was trying to mount an external drive connected thru usb-c. It would not show up at all after multiple tries. I tried logging off and logging on and still nothing. I did notice that the screen briefly flashed when I plugged in the drive. Finally I rebooted and then I saw a dialog asking me if I wanted to accept the external drive (not sure of the exact wording.) The drive then mounted. Subsequently, I saw the same problem again, including the flashing screen. This time I was able to observe the dialog box appear for just a very brief time before disappearing. After trying the log out, log in method to no avail, it occurred to me that another admin user was also logged in. I switched to that user, and the dialog box appeared without issue and I was able to get the external drive connected.
Has anybody observed this? Is there any way to disable this dialog or make it behave better? I suspect this may be difficult to trouble shoot as, once drive is accepted, it seems to mount without the dialog box regardless of the primary, front window, user. BTW, I DID check diskutil and it was not showing up at all until it did finally mount, so MacOS was not even acknowledging the drive’s presence before it finally mounted.