Really bothers me this is not deterministic
Different PCs and OS versions will give different files
So here I am, "formatting" all the images for no reason after switching OS
* desktop: restored automatic power off & manual power off on slideshow view; assets: added frames for new first start sequence; docs: added info on slideshow compilation
* desktop: restarting long timer on OK button release
Co-authored-by: あく <alleteam@gmail.com>