During normal restart, I ended up with the kindle tree screen.
I have jailbroken the kindle and updated to 5.10.2. Everything was working fine and have previously successfully restarted it.
I have held down the power button for 40 seconds and the screen kinda flashes but then doesn't otherwise do anything.
Hope I didn't accidentally brick it :\ .. and trying not to panic
... only thing i can think i may have changed was setting up usb networking to launch on startup. but of course i had the device in airplane mode before restarting :\
battery was at 90% before the restart.
and right now its plugged in to the wall outlet and the green light (full charge) charge indicator is on. but still seeing the guy under the tree reading the kindle.
-----
update ; finally seems to be booting. man that gave me quite a scare. anything i should change/do differently to prevent this from happening? ... never restart it?