Mbed OS on Adafruit nrf52840 feather express

I’m trying to see if I can get a simple Mbed OS based application run on the Adafruit nrf52840 feather express board. I tried compiling with the target set as NRF52840-DK - the code compiles fine.
Also, I’m able to push the blinky example on the DK board, and it seems to work fine. But I’m having trouble with the Adafruit board. Mbed Studio doesn’t recognize the board when I plug it in. And mbed CLI is also not able to detect the board.

Has anyone tried porting Mbed OS to Adafruit nrf52840 feather express? Any pointers would be appreciated.