iOS/Android – Image shows as broken in chat right after upload (local attachment cache copy fails with ENOENT)

[MelvinBot]

Platforms: iOS and Android (native apps)
Version reproduced: 9.4.51.1

Problem

An image posted in a chat renders as broken immediately after sending, even though the upload to the server succeeds. Reopening/refreshing the chat renders it correctly, because the file is safely in S3 — the broken state is purely a local cache miss.

Root cause

After a successful upload, the app copies the just-uploaded file from its temp Receipts-Upload/ folder into the local attachment cache. The temp source file is cleaned up before the cache-copy step runs, so the copy fails and the image renders broken. This is a race condition between temp-file cleanup and the cache-copy step.

On iOS the failure surfaces as:

[AttachmentCache] Failed to cache attachment
error: code 'ENSCOCOAERRORDOMAIN4' (NSCocoaErrorDomain 4 = file not found)
  copy .../Receipts-Upload/<uuid>.jpg → .../attachments/<id>.jpg
  underlying: code 2 (ENOENT)

Expected

The image should render immediately after sending, without needing a chat refresh.

Actual

The image renders broken until the chat is reopened/refreshed.

Scope (production logs, 2026-08-12)

• 747 occurrences today across 404 unique users, steady throughout the day (no spike) — pre-existing, widespread iOS/Android issue, not a today-only regression.
• Example failures (iOS 9.4.51.1): request a29c525a0c270999-SJC (03:16:30Z) and a29c53021d2a0999-SJC (03:16:57Z).

Related issues

• Android/iOS - The image attachment is not cached on Android and iOS devices #85604 — "Android/iOS - The image attachment is not cached on Android and iOS devices" (open). Same subsystem/mechanism; likely the same root cause, but framed around the cached file missing from the device folder (found via QA) rather than the user-visible broken-image-on-send symptom.
• [$250] Attachments - Markdown image URLs are not cached #85557 — "Markdown image URLs are not cached" (possibly related, same caching area).

Reported by @mallenexpensify via DM with MelvinBot.