Sometimes, a Chapter field (Insert - Fields - Other, Documents tab, Chapter)
does not reflect the character heading level specified in "Layer", but a higher
level. Steps to reproduce the problem

* Open a new document
* Insert a Heading 1 formatted paragraph
* Insert a Heading 2 formatted paragraph
* Insert Header - Default
* Insert in the header a chapter name: Insert - Fields - Other , "Document tab",
Type: chapter, Format: "Chapter name", Layer: 2

It already goes wrong here: the Heading 1 formatted entry appears rather than
the Heading 2 formatted entry. There is a Heading 2 formatted paragraph on this
page here: that is the one that should be reflected in the header.

On subsequent pages, the Heading 2 level is correctly displayed. However, when a
new Heading 2 is inserted e.g. somewhere halfway the page, the old header is
still displayed rather than the new one.