Here’s another one that I already posted in the official bug reporting section four months ago:
if I include multiple images with the same exact content, then only one will be included in the ebook, the rest will show a broken image.
How to reproduce: create an image, let’s call it “a.jpg” and simply copy/paste it in Windows, to create “a (Copy).jpg” or rename it to “b.jpg” it makes no difference. Now include both “a.jpg” and “b.jpg” in the document (two different files, but their content is exactly the same). Compile a kindle ebook. It will give errors that files with extremely strange names are not found. And the end result will be that only the first image is included in the mobi file.
Details in the bug report thread: https://forum.literatureandlatte.com/t/same-image-multiple-times-fail-when-compiling-ebook/48407/1