This is awesome

Does your SD card reader itself show up in lsusb? Does anything extra show up in /dev when plugging it in? It may be that there’s no partitions on the drive, so you don’t see any storage. Could also be either your reader or card not working, however. It would help to get another reader or card to test if your reader or card work.

These are really well made, no webgl no webgl in some games, no html5 canvas, just good code.