epub3 fixed layout conversion

[Ghost-Terms]

I have an epub v3 file that has a fixed layout. The only reader I've found that can even read it at all is Thorium Reader which uses the readium-js library for epub rendering.

Unfortunately there isn't a way to print or convert an epub file in Thorium Reader and it's honestly fairly clunky to use. Trying to convert one with Calibre is a mess and it doesn't look like they're going to be getting any support for it any time soon.

Given the nature of this project, converting things to 1:1 cbz files, I was wondering if you could possibly add support for this.