[Solo1959]

I re-installed Calibre on my new computer and I am having a problem with Chapter numbering inside mobi ebooks. It is possible that I fixed something many years ago on my old computer that I need to fix again on this computer. If anyone can advise, I would appreciate your help.

When I convert any document - docx, odt, epub, azw3, txt - to mobi format my chapter headings in the book will display with a leading number:
1. Chapter 1
2. Chapter 2

When I convert to any other format, the chapter numbers will display correctly without the leading number:
Chapter 1
Chapter 2

There is nothing different in the conversion screen [Metadata, Look & Feel, Heuristic processing, etc.]

I can't figure out how to prevent the leading numbers from the Chapter heading. As i wrote, this did not happen on my old computer, but it is happening every time on this new machine. That leads me to believe that I set something incorrectly.

Thank you in advance for your help.