That's awesome! Up until now the only reason I have jailbroken every kindle I've owned is to have the screensaver be the book I'm reading rather than the dull preset ones. Finally I've found reason 2!
> Dou you prefer to just show the last thing that was on screen, with an overlay indicating when the device's alseep? Just drop a blank file named last in the linkss folder. Restart your Kindle ([HOME] -> [MENU] > Settings -> [MENU] > Restart; or simply use the Screen Savers > Restart framework now button in KUAL), and you're done
from https://www.mobileread.com/forums/showthread.php?t=195474
Obviously make sure you read everything (really, everything, including all the tiny text, even if it doesn't seem relevant) before you start.