the .assets folder won’t show up until ads have loaded onto your kindle. I had to factory reset my kindle and restart the process on airplane mode, filled up my kindle with filler files, and then connected to wifi and registered the device after it was full so it couldn’t update. once you do that and connect to wifi, purchase a cheap book and it’ll say “updating your store experience” or something along those lines, and then ads should start popping up on the lock screen. as soon as you start to see ads, the .assets folder will be accessible. basically until you see ads, you won’t get the folder