Recently I bought the TP-LINK Archer T3U Wifi usb key (2357:012d). The driver is not included in my current kernel (5.1.4-arch1-1-ARCH) so I tried to install it:

sudo pacman -S core/linux-headers gcc
yay -S aur/rtl8822bu-dkms-git

I came across the problem described here

The good news is that its works well for me with 5.3.6.arch1 kernel.