Error adding/amending footnote with Zotero

Hi there,

I’ve been getting an error message when I try to amend or add a footnote using the Zotero plugin. I have attached screenshots of the error messages I have been receiving.

image description

They all seem to be variations on the same theme.

I have tried:

After I try adding or altering a footnote the system hangs for a bit (maybe 30 secs) then I get the dialogue box stating that a footnote (later on) has been modified and do I want to keep the changes or lose the changes so the footnote keeps updating. Regardless of which option I select the attached error message appears.

The document is fairly lengthy and was previously merged, incorporating tracked changes from two authors and many comments throughout the document. That said, the file size is still only 1.8mb.

Thank you, in advance, for any help or assistance you can provide.