[arpeggioaccele]

That makes sense. It does seem useful when I want to test out various different conversion options, as the EPUB file is overwritten each time. Maybe the problem is that it is unclear from anywhere but tweaks that original_EPUB will be used as the conversion source.

I think my specific issue was that original_EPUB is also used when going from one source to a different source too, which is not described in the Tweaks description. When going from EPUB to PDF, if original_EPUB is present then it will be used.

Even if I were to use original_EPUB only temporarily only for testing conversions, I would have to keep replicating the same settings twice to get the EPUB and PDF outputs.

Right now, I am doing the original to EPUB conversion, using the editor on the EPUB file (which does not recognize the original_EPUB file) to replace the publisher's CSS, then EPUB to PDF for inverted colors. It was simpler to input all the settings once, not twice.

Perhaps there is a simpler workflow I am unaware of though.