I use macOS so it a looks a bit different, however the internal storage remains empty if you have selected the SD Card as your file destination.
I normally remove the SD card and stick those in the back of my iMac for 10 times faster transfers so I hardly get to see the drone's internal storage. But when I connect the drone to the iMac via the UCB-C port on the aircraft, the internal also appears on my computer. Shows up empty as explained, because I always use the SD card.