My documents somehow changed on it’s own from single view to double view. How do I get it back on the latest version
of LibreOffice Writer?
Bottom right on the Status Bar are three icons looking like books; click the left one to return to single page mode. From left, they are single page view, multiple page view and book view; hover the mouse pointer over them for a help bubble (tool tip).
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However, this will not permanently stop LOo from sometimes re-opening documents in multipage view, at least after a crash, for which default view I find no setting for.