(In reply to Kris Taeleman (:ktaeleman) from comment #3)
@botond: I think you've looked at this before, any thoughts?
I think restoring the zoom level and the visual scroll position should "go together", i.e. we shouldn't do one without the other.
Whether we restore them or not is largely a UX question. My personal feeling is that restoring them is consistent with the current behaviour of restoring the layout scroll offset (after all, the distinction between the visual and layout scroll offsets it's largely an implementation detail and not particularly relevant to the user), and that it's a useful behaviour. Causing problems for dynamic sites could be a reason not to do it, or to try to detect dynamic sites and behave differently for them, but I don't have a good sense for the prevalence of this issue.
(In reply to Kris Taeleman (:ktaeleman) from comment #7)
From a browser comparison perspective, it does seem like we should restore the zoom position, but maybe this can be done for the follow-up releases and we reset the zoom for now?
That sounds reasonable to me (especially as reliably restoring both requires bug 1525259 which we've already postponed to desktop-zoom-post).