Previously I had written a post about the same driver RTL8723de which you can find here. It works perfectly on systems with Linux kernel versions upto 4.14. But unfortunately for kernel versions later than 4.14 that solution won’t work. For example if your wifi device is RTL8723de aka RealtTek d723 then after the upgrade of Ubuntu from 16.04 LTS to the latest Ubuntu 18.04 LTS wifi will stop working. Now that I have found another working solution for kernel versions later than 4.14, I shall share that with you now. Please note that this tutorial uses another repository than the one mentioned in the previous post. Also, it uses the extended branch and this driver is not available in the master branch of that repository. I have tested it personally and ensured that it is working fine in kernel v4.15.
So here are the steps to install wifi driver for RTL8723de in Ubuntu 18.04
Clone the repository
git clone https://github.com/lwfinger/rtlwifi_new.git
Checkout to the extended branch
git checkout extended
Enter to the cloned folder
sudo make install sudo modprobe -r rtl8723de sudo modprobe rtl8723de
That’s it! You have now successfully installed RTL8723de wifi driver on your Ubuntu 18.04. This repo also contains driver for RTL8723be and much more RealTek devices.