The endpoint hunt is done guessing. Results:
/files/{libfile}/download 200 {"error_code":"file_not_found",
"error_type":"GetDownloadLinkError"}
— twice, on two different Library ids, so the
Library id is simply not valid there
/library/* 404 across every shape
POST on the download route 405
/content?asset_pointer= 422 requiring query params id, ts, p
That last one is the find: /backend-api/content is a signed route, and the
web UI has the values we cannot compute. So the question shifts from "which
endpoint" to "is the UI's URL reusable outside the browser".
try_pasted_url.py takes a URL copied from DevTools and fetches it three
ways — bare, through the exporter's authenticated session, and with the
Authorization header removed in case bearer and signature conflict. The
pattern says whether the exporter can fetch these at all, and therefore
whether it is worth hunting for what mints the signature.
Before any of that: check whether the images still render in ChatGPT's own
UI. If they show broken there, file_not_found is literally true, these 11
are lost like the other 7, and no route exists to find.
