No Webcam Driver - XPS 13

@NatKemp  You didn't mention which specific model of XPS 13 you're using -- there have been several generations of the XPS 13 over the years -- but for the last several years laptop webcams have just used a standard driver built into Windows rather than requiring a special driver to be downloaded.  However, if you're not seeing a webcam in Device Manager or an unknown device either, then it means that the device isn't being detected at a hardware level, in which case even if a special driver was required, it wouldn't help at this stage.  I would check in the BIOS to see if it might be disabled at a firmware level.  Otherwise, the connector cable onto the motherboard might be loose.  If the system is under warranty, you may want to contact Dell Support.  If not, you can get the Service Manual at support.dell.com to see how to open the system up and check the webcam cable.  Be careful though, because many of those ribbon cables are fragile.