Footers and headers are attributes of page styles and stored in them. This presents no conceptual difficulty in simple documents.
But wit master/subdocuments, you must modify the active page style, knowing that attributes set in a subdocument do not forward to the master. The master uses its own page styles which only share their name with those in the subs. In other words, page styles in master are independent of those in the subs, even if they have the same name.
You can take advantage of this to add comments, reminders, caveats, instructions, … in header or footer of the subdocument.
The “real” header printed with the master is the one you set in the master page style(s).
Write your additional line in the master footer:
- enable
View
>Formatting Marks
and View
>Text Boundaries
(not mandatory but very convenient to see where thing are located; the clues do not print, so you can let them always enabled)
- click in the footer
- make all you editing
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