[mallomar]

Originally Posted by BetterRed

Latest calibre version is 8.6 ==>> https://calibre-ebook.com/whats-new

BR

Thanks, I mistyped, it's Calibre 8.6

Originally Posted by DNSB

Is the calibre version a typo? It is 10 major versions ahead of the current calibre 8.6 release.

And the MacOS Sequoia version would appear to be a beta.

Yes, a typo and yup, you're correct, it's a beta, though I don't imagine that's having an impact here.

Originally Posted by DNSB

As for the difference between using the calibre conversion pipeline and the KFX Input plugin? What you are running into is the same reason I use the KindleUnpack plugin for azw3/KF8. The output ePub generated by KindleUnpack is a lot closer to the original ePub input to KDP than is the output from the calibre conversion pipeline. OTOH, the calibre conversion can handle a lot more formats. That it can munge the structure, CSS, etc. of an output ePub from the semicompiled KFX or azw3/KF8 input is something that you may have to live with if you are going to insist on using calibre's conversion pipeline.

I suspect that you are not going to see any major changes in the calibre conversion pipeline since that would be time intensive with testing required on multiple formats both input and output.

Thank you, I've been using boh KFX Input's KFX to EPUB and Kindle Unpack's KF8 to EPUB because of these same reasons, but I figured these two plugins handling it better than Calibre must be a bug in Calibre. I've been using Calibre for over a decade (since 2014) but I am not a developer and do not deem to understand all of its many intricacies.

Originally Posted by kovidgoyal

KFX isnt a supported format in calibre, except via the third party KFX Input plugin. You should report the issue in that plugin's thread.

Thanks, I thought KFX showing up in Calibre's conversion menu meant it's being handled by Calibre, but I guess not? What is handling the conversion if it's not Calibre and KFX Input's convert to EPUB gives different results?

Originally Posted by jhowell

I am willing to look into it if you provide the files that exhibit the problem.

Sure, we discussed one book here. I am attaching the scrambled EPUB from Calibre's conversion engine and from KFX Input's Convert to EPUB. I have also noticed the problem recently in two other books – Big Swiss and Chain Gang All Stars. I am attaching the scrambled KFX Input and Calibre Engine conversions for those as well.