This is my own revision of the driver, available from D-Link/Realtek, for the RTL8821CU chipset to make it functional on the Linux 5.9 Kernel. Other branches include the relevant patches to make it work on kernels 5.6 and 5.8.
I provide no warranty with this code, as I only made the modifications so that my DLink DWA-171 USB WiFi Adapter is functional on ArchLinux. That said, maybe the modifications I made may prove useful to you.