It might be possible to insert a SET field. This creates a bookmark in the document to which you can assign information. However, there is no way to protect him from the user deleting him. The DATA field is also possible.
Unlike “fade” (which, I believe, is equivalent to a “hidden” font), information will not be displayed if the user is used to display non-printed information. It will be displayed, however, if the user switches to field codes (Alt + F9).
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