Thanks VS. But let me get this straight: aren't they Unicode codes? Doesn't that require the original document to be saved specifically as Unicode for these to display correctly?
What are the other ones I quoted, then, and why would they show up? I've seen them before showing up in documents in Microsoft Word (for instance), and assumed they were something to do with coding, but other than doing a find-and-replace on them didn't really know how to fix them. What are they, exactly?
And why would editing the file in Sigil - not changing either the body copy or the CSS, but simply embedding a jpg file as the cover - makes these weird codes show up?