I realize now that "miniatyrer" is the option that is called "thumbnails" in English versions of Word. Word 2007 offers a check box for the Document Map and one for Thumbnails, while recent versions have both options in the Navigation pane.



Assuming that you selected the "Document Map" option, it should be enabled even after you close and reopen Word. I don't know of a situation where Word would force the display of thumbnails instead. I can imagine that it would happen in a document that has no heading styles applied to text, but I haven't been able to reproduce that.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional