Issue 68634

When I enter the Print preview mode, Writer sets 48% zoom factor automatically
(it shows two facing pages at a time). At this zoom factor, when I use the mouse
wheel to scroll up/down, the pages are displayed in exactly the same position.

However, this "non-standard" zoom factor is lost when I use controls to zoom
in/out. Now the nearest "standard" zoom factor is 50%. But at this zoom factor,
the pages start drifting upwards/downwards when I scroll up/down.

I mentioned this to demonstrate that Writer already has the capability to
display the pages in "single page" and "continuous" modes, as in Acrobat Reader.

The only problem is, we can't control the behavior: The change is involuntary.

Please provide "single page" and "continuous" buttons in the GUI, so that we can
change the display behavior as desired.