[democrite]

Thanks for mention of the plugin. Looks interesting.

Haven't tested much though when I make major changes to NAV, I prefer a copy of the original, set as linear="no". I may remove other nav elements such as list of tables, figures, etc., remove, modify, or re-create them.

The plugin too as you know, adds new hidden elements. Sometimes an id maybe in a separate element from TOC destination; seems in such cases when a hidden element is added. Changing the structure w/such new elements messes up locations, such as highlights, annotations, external links, etc. when in cases when I may make corrections/edits and then replace the original in some reader.

Maybe other issues. I still prefer a backup of original nav/ncx just in case. Maybe the plugin could be improved by instead of hidden elements, creating comments. Yet, my request was just a minor thing in some specific case of renaming the last file, spine position changes. A fix someday would be great if possible.

Overall, it's the refinement of various things I wish were better. e.g., to convert to EPUB3, I'd prefer one step, one shortcut or menu item, then save, done, without the various additional mouse movements, clicks/taps, keystrokes, replacing original in file manager, reopening, again setting sigil norm, etc.