I set up all headings in styles 1,2,3. Do I have to actually create a TOC, or is that something that gets generated automatically?
I encountered many problems with heading 3 at Lulu. Now I just avoid them altogether. I give them a different style name like "bold three". Avoid numbers in styles. This will also trigger errors in Sigil. Update TOC (generate toc) after every change otherwise you will get an "invalid" notification when uploading.
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