Nordic "nRF52840 Dongle" Support

@Gordon Saving code to the dongle doesn't work , but works on the nRF52840DK.
Tested save() and "Write To Flash" (from the IDE), neither works on nRF52840 dongle, but both work on the DK. Tried two builds on both: 2v04.33 and 2v04.121 (current latest), same behaviour.
I know neither is an official board, but any idea?

The DK:

>setInterval('LED2.toggle()', 333);
=1
>save()
=undefined
Compacting Flash...
Calculating Size...
Writing..
Compressed 200000 bytes to 6277
// And works just fine

The dongle:

>setInterval('LED2.toggle()', 333);
=1
>save()
=undefined
Compacting Flash...
Calculating Size...
// hangs there, and disconnects after a couple of seconds.
// nothing saved to flash, works just fine after power cycling...

Edit: thanks for the previous reply, of course I want to do something totally not supported with the pins :)