Tracking changes in the bibliography
On average, we create Word documents containing between 20 and 200 references. These documents are updated regularly and all changes must be visible in track changes mode. Unfortunately, when references are deleted, replaced or added, this is not currently visible in the bibliography. Is there a way to make these changes visible in the bibliography?
Upgrade Storage
If you paste the current bibliography as text-only (without Zotero field codes) into its own document prior to updating the main document bibliography, and then do the same with the new bibliography after Zotero updates it, then MS Word's Compare operation can compare the two documents you created. It can add tracked changes into either document or a new, third document.
https://www.johngarger.com/blog/create-a-track-changes-document-by-comparing-two-microsoft-word-files
If you keep the plain-text second document from the process, that will become the original bibliography document the next time you update your bibliography and need to repeat the process.