Oh, I don't doubt the functionality of your advices, but I thought more of an advice like "of course, you can modify calibre's behavior by visiting the settings pane..." Or "copy the EPUB_output.DLL of version 3.29 over your current installation files". Ain't there an easier way to change calibre's behaviour for EPUB's to pre-3.30 ways, that sounds like much manual work for me.
Can anyone tell me if this is unwanted calibre behavior as davidfor pointed out earlier, and how do I create chapters in the HTML form?
@theducks: unfortunately, I didn't get the way you performed your tasks. Could you elaborate on that with screenshots or a link to an FAQ?
@DNSB: the book in this screenshot (
https://drive.google.com/open?id=1sQ...iN6ry0WEsuX4n4 ) is my EPUB file, opened with sigil, that creates these problems. It has been converted from the HTML file to EPUB with calibre.
However, after the second time converting the file, EPUB to EPUB, Sigil complaints about "not well formed HTML", and the images in the file seem to have disappeared from the html view in sigil.