Hello,
I'm running calibre 4.11.2 on Windows 10 and am having an issue converting the book "Chess Endgame Workbook For Kids" with Amazon ASIN B07ZKDCTJJ.
When I attempt to convert to PDF, the process will run for hours while making no progress. Converting to other formats completes within a few minutes.
There is a secondary problem that may be related. The book contains svg images of chess boards that require a special font to be rendered properly. I see the proper font file unpacked as /fonts/0001.otf. There is also a style.css file which refers to this file.
When converting to PDF, the process never completes and appears to deadlock. When converting to other file formats, the process completes after a couple of minutes but the converted images do not use the chess font.
For more information and a full conversion log, please see the bug report at
https://bugs.launchpad.net/calibre/+bug/1865380
Note that the new piece of information I have since filing that report I now realize that the hang occurs always and only when converting to PDF.
Thanks for any help you can provide.