Created attachment 202503 [details] test file I assume DOCX doesn't support the feature of having comments within footnotes as Word 2016 doesn't permit you to do it, though ODT and Google Docs does. So when exporting a DOCX from Google Docs with a comment in a footnote, the corrupt file dialog appears and if repaired, the file will open as it is intended to, except for the comment being blank.
Created attachment 202504 [details] how the file looks like in google docs
Confirm the missing comment from the footnote. Version: 25.8.0.4 (X86_64) Build ID: 48f00303701489684e67c38c28aff00cd5929e67 CPU threads: 16; OS: Linux 6.14; UI render: default; VCL: gtk3 Locale: ro-RO (en_US.UTF-8); UI: en-US Calc: threaded