A couple years ago, I was looking for a pair of 20", standard aspect-ratio monitors. There wasn't a huge selection available, and I ended up with a SyncMaster 204b, and an XL20. I didn't realize that the XL20 would be treated simply as a generic PNP monitor, and I have been unable to find any path toward convincing Windows 10 to remember that it is there.
It has always come up reliably, because I just keep a Control Panel window open, and click on the Detect button every time the computer boots or wakes up. If anyone has any suggestions as to how I could get that to show up permanently, though, I would really appreciate it.