Devices using the Realtek Semiconductor Corp. RTL8812AU 802.11a/b/g/n/ac WLAN Adapter, require drivers that have not been merged with the linux kernel and do not come with most linux distros(yet). Follow this guide to install them yourself!

Make sure you have the required build packages

sudo apt-get install linux-headers-generic build-essential git

Download the updated source code

git clone https://github.com/scrivy/rtl8812AU_8821AU_linux.git

Compile the kernel module

cd rtl8812AU_8821AU_linux
make

Install it!

sudo make install
sudo modprobe 8812au

plug in your wifi adapter and enjoy!