TP-Link T3U WiFi dongle not working on piCorePlayer

I can't get a TP-Link Archer T3U Plus wifi dongle to work on piCorePlayer 8.2. This dongle is based on RTL8812BU chipset.
The diagnostics page says "No wifi devices found!",
Wifi is set to "On", RPi built-in Wifi is set to "Off".
Is there a way to fix this issue?

Note: if required, I am able to compile and load a Tiny Core module.