Taking Egg's approach further, I decouple my NavBars from the page entirely and embed with things like:
The inner IFRAME is just for IE/Edge. The OBJECT does a cleaner job in newer browsers.<object type="text/html" data="index_htm_files/menubar embed.htm" width="100%" height="100%"><iframe src="index_htm_files/menubar embed.htm" width="100%" height="100%" style="border:none;"> I'd give up!</iframe></object>
The NavBar page does not have (need) HTML, HEAD or BODY tags.
Doing it like this allows simple text editor changes.
Acorn
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