in resources/asciidoctor/lib/chunker/find_related.rb [47:61]
def find_next_in(parent, index)
loop do
while (c = parent.blocks[index])
return c if c.context == :section && c.level <= @chunk_level
index += 1
end
return unless parent.parent
return unless (index = parent.parent.blocks&.find_index parent)
parent = parent.parent
index += 1
end
end