Extremely slow RTL8188CUS WiFi in 15.3

I have a Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter and it has become extremely slow in 15.3. I had to apply this workaround:

modprobe -r rtl8192cu  
echo "blacklist rtl8192cu"  >>  /etc/modprobe.d/blacklist.conf  

https://askubuntu.com/questions/1144019/wi-fi-adapter-realtek-rtl8192cu-slow-speed-connection-0-5-mbit

After disabling rtl8192cu it is working fine. However, as you can imagine, downloading anything during the installation took ages. Fortunately, most was on the DVD. At times I had download speeds of tens of kb/s.

Question:
Which driver is running for that Chip?

PS:
I would use a better named blacklist file, f. e. 50-blacklist8192cu.conf