Dear Maintainer,

* I am writing a book. So far 36896 words are written including Pandoc
ePub YAML tags for the header.

* The preview is set to the markdown flavour Pandoc

* I noticed that the text shown in the editor are not in sync.

* My workaround is to click on a subtitle in the sidebar to sync with
the preview - although it is not that precise and I have to scroll up a bit

* From my point of view, it would be way faster anyway to preview only
the markdown-text actually shown in the editor instead of a preview of
the whole book. This might have some drawbacks I do not know of so far.
This idea is deriving from the windows software mardownpad - see
screenshot on website (http://markdownpad.com)

Kind regards, Simon