Using Surface Laptop 3 with LG 5K Ultrafine monitor ...
I have traditionally used Macbook Pros and had an LG 5K Ultrafine monitor connected with USB-C Thunderbolt 3. When I try to connect the Surface Laptop 3 to the momitor I get a Windows message of: USB or Thunderbolt device functionality might be limited, Make sure the device you're connecting to is supported and that you're using the right cable ...