Here's a fix that
should work when converting to KFX with negative margins causes some center-aligned text/images to left-align instead. Use the CSS below, preferably added directly to the top of the main stylesheet in the "Edit Book" interface.
Code:
html{
margin-left: -30px;
margin-right: -30px;
break-inside: avoid !important;
}
I've only tested this with a couple of books, but the CSS above fixed the issue in each one. Adjust the margin values to your preference.