So yeah, because my Paperwhite is already running firmware version 5.3.4, I cannot successfully uninstall jbpatch 3.2.1 before upgrading to 4.0.0. Just as that version doesn't work under the new PW firmware, neither does the uninstall utility which returns an error.
So instead, I just installed 4.0.0 over what I already had in place which seems to be working fine. But so that I have as clean an installation as possible, I wanted to verify if there was any other cleanup I should do, stuff that might still be lying around from 3.2.1 but has been pulled from the 4.0.0 build as pertains to the Paperwhite?
Thanks again for all your great work on this tool.
Edited to Add - maybe
opt/jbpatch/com.mobileread.ixtab.patch.fontsize.jar might be an example of something I should clean up/remove? I see it's still there albeit with an older date and I remember reading it's not valid for the PW any longer.