Originally Posted by stewacide
I can easily get Calibre to make a white-on-black version my converting with a bit of added css, but I can't figure out how to get Calibre to not then replace the old black-on-white epub; instead I want them to co-exist.
I have not much experience with Calibre. I therefore can only guess. 1) rename the epub file, 2) rename the dc:title in the opf file, for instance by adding "(white on black)" 3) rename the cd:identifier in the opf file. I am not sure whether all three points are necessary.