Camera RAW (V15.5.1) stuck on one monitor, unable to move

There is no solution to this. The question has been asked many times and Adobe has not offered a fix. Basically (usually if you enter Camera Raw filter while the document is saving) the application gets stuck in the Camera Raw filter and all you can do in the end is just force quit and hope it recovers. Folks have suggested that you deactivate the option to "export clipboard" in your preferences, but this is not a fix and does not work (may have worked for a few folks but it is not a fix, nor should it be). You cannot even access the settings of photoshop when you are stuck in Camera Raw so I fail to see how it was ever accepted as a correct answer. The only solution, thus far, is to force quite the application and try to let a document fully save before enterign the Camera Raw filter.

Try resetting your ACR preferences, better? 

Hold down the Command key and select Photoshop > Preferences > Camera Raw (MacOS) or hold down the Ctrl key and select Edit > Preferences > Camera Raw (Windows).

Click Yes in the dialog that asks "Delete the Camera Raw Preferences?"