Has your Ethernet connection stopped working when using macOS exclusively? Chances are, it’s not your motherboard, data cable, or Internet connection and is due to the kernel extensions that you recently installed. We discovered that IntelMausiEthernet.kext (not to be confused with IntelMausi.kext) was broken and thankfully knew how to correct it since the Intel-based Bluetooth/Wi-Fi combo card that was shipped from Dell lacked support for Wi-Fi under macOS.
I have converted a few Windows laptops to HackBooks and to make things easy, I always swap out the internal Bluetooth and Wi-Fi combo card and while trying to turn a Wi-Fi router into a Wi-Fi repeater, I discovered that the Ethernet connection was no longer working.
The best solution would be to downgrade to the last working version but since I had no clue when it happened as I was mainly on a wireless connection, the alternate thing for me now was to patch since a downgraded version would cause a constant notification from the Clover Configurator app that a newer version of the kext has been released and would cause me to accidentally download it again. Other alternatives are to make sure that FakeSMC.kext is updated (be sue to backup if there is a later version available or switch to IntelMausi.kext