rschroll
commented
10 years ago "Back" undoes navigations other than simple page turns, e.g. following hyperlinks or changing chapters. This is very useful when viewing endnotes, a glossary, or a dramatis personae, to return to the place you had been. "Forward" undoes "Back", and is therefore only enabled once you've used "Back". You're not apt to use either very often, but they're nigh indispensable in those cases where you do use them. If there's some labels that make this behavior more obvious, I'd love to hear them.
The fact that the API uses "Back" is annoying not only here but in the web browser element as well. It'd be much better, in my opinion, if it said "Return", or maybe nothing at all.
stuartlangridge
I don't understand what "Back" and "Forward" do in the book toolbar. They don't seem to jump between chapters -- indeed, "Forward" is disabled a lot of the time. It's also extremely confusing to have two buttons labelled "Back" in the toolbar, one of which does this unknown thing and the other of which goes back to the book list! I spent a good five minutes earlier today baffled by how I couldn't get back to the book list and my book kept jumping around to different positions before I realised that I was pressing the wrong Back button.