A User of Table of contents
December 11, 2019
i maintain several large GDocs, one of them more than 160 pages, and this add-on has been a huge help. Browsing through the document through the built-in outline view is faster (it responds to clicks on section headers much more quickly), but this one's ability to renumber all sections has been a tremendous help.
If you find that it won't open for you: disable your browser's ad blocker in GDocs, as ad blockers interfere with legitimate GDoc features.