This is the code that 'Insert Sigil Capter Marker' places at the insert point.
Code:
<hr class="sigilChapterBreak" />
I frequently use a REGEX search&replace to place this before the 'Chapter heading' code,
then I press F6 (once on each 'section' I have coded). a Very quick way to make a 'Chapter per file(section) book. A few manual edits for other types of sections and
all done.