(Apologies if this is covered somewhere, I did a quick search in the postings without any hits.)
I'd like to be able to add a line within the <guide> section of the .OPF file:
<reference type="toc" title="Table of Contents" href=... />
This allows calibre to connect a Table of Contents on the Kindle.
I'm happy to do it by hand, but I can't figure out any way to get to the .OPF file within Sigil. I can explode the .epub file and edit the .OPF file and re-zip, but that seems inelegant and awkward.
Is this possible with the current beta?