I have had issues running a wifi dongle when connecting using the tv's usb port - admittedly this is with the old version and not the new one with the updated power circuitry.
However, I have had no issues using usb power from the tv with a LAN connection - this is using Kodi which I suspect will increase the power pull. YMMV
However, I have had no issues using usb power from the tv with a LAN connection - this is using Kodi which I suspect will increase the power pull. YMMV