The problem with custom screensavers in the native GUI (i.e. not in KOReader) is that tampering with them is risky; if you put your own files in the /usr/share/blanket/screensavers folder (which is where the screensavers are stored) and the files are not in the correct format, your Kindle might refuse to boot.
This was all properly handled in the past by NiLuJe’s Screensavers Hack, but this hack doesn’t work on firmware versions higher than 5.16.2.1.1.
Now, not all is lost, as there is a
tool to convert images to a compatible format, but this format varies across Kindle models, and there is no automatic check that your converted files will work on your specific Kindle.
If you’re willing to get down to the nitty gritty of finding out the correct format, converting your images and uploading them to your Kindle via ssh, there is a thread on Discord with a lot of information on the topic; you can find it here:
https://discord.com/channels/1083603...89065998585897