Attachment can stay stuck with "Downloading..." state even across client restarts #7989
Description
Apparently an attachment can stay stuck with "Downloading..." state even across client restarts. This can happen with both DeltaTouch and DeltaChat desktop, see here for both:
- Operating System (Linux/Mac/Windows/iOS/Android): postmarketOS Edge
- Core Version: v2.43.0
- Client Version: deltachat-desktop and deltatouch both affected
Expected behavior
The download should fail and allow me to click "Download" again if there is no more progress being made for a notable amount of time. Especially after a client restart, which I assume interrupts the download process entirely. Also, it seems like given how small the download size is, that this isn't really some sort of network error but rather some error happened parsing the attachment, which I would expect to be shown to me.
Actual behavior
The download seems infinitely stuck, and neither can I retry nor is it clear what the problem is since this attachment should have downloaded in less than 1-2 seconds even using my awful connection here.
Steps to reproduce the problem
- Not sure how exactly this faulty attachment happened that resists downloading. But once you have one I imagine you'll see the same bug
Screenshots
See above
Logs
It seems like it might actually be continuously retrying in the background, I'm not sure:
2026-03-15T10:24:31.549Z core/event WARNING "" 1 "src/download.rs:285: Failed to download message rfc724_mid=73bc616d-e126-40a4-b07f-042a8224038b@localhost: IMAP location for \"73bc616d-e126-40a4-b07f-042a8224038b@localhost\" post-message is unknown."
2026-03-15T10:24:31.866Z core/event WARNING "" 1 "src/download.rs:285: Failed to download message rfc724_mid=73bc616d-e126-40a4-b07f-042a8224038b@localhost: IMAP location for \"73bc616d-e126-40a4-b07f-042a8224038b@localhost\" post-message is unknown."
2026-03-15T10:24:31.873Z core/event INFO "" 1 "src/imap.rs:1207: FETCH result contains no UID, skipping"
2026-03-15T10:24:31.878Z core/event INFO "" 1 "src/scheduler.rs:566: IMAP session in folder \"DeltaChat\" supports IDLE, using it."
2026-03-15T10:24:31.880Z core/event INFO "" 1 "src/imap/idle.rs:37: Skipping IDLE in \"DeltaChat\" because there may be new mail."
2026-03-15T10:24:31.882Z core/event INFO "" 1 "src/scheduler.rs:630: IMAP loop iteration for Mvbox finished, keeping the session"
2026-03-15T10:24:31.883Z core/event INFO "" 1 "src/imap.rs:596: fetch_new_msg_batch(DeltaChat): UIDVALIDITY=1720446198, UIDNEXT=517667."
2026-03-15T10:24:31.946Z core/event INFO "" 1 "src/imap/select_folder.rs:80: Selected folder \"INBOX\"."
2026-03-15T10:24:31.955Z core/event INFO "" 1 "src/imap.rs:791: 0 mails read from \"DeltaChat\"."
2026-03-15T10:24:31.958Z core/event INFO "" 1 "src/imap.rs:800: available_post_msgs: 0, download_later: 0."
2026-03-15T10:24:32.019Z core/event INFO "" 1 "src/scheduler.rs:566: IMAP session in folder \"INBOX\" supports IDLE, using it."
2026-03-15T10:24:32.021Z core/event INFO "" 1 "src/imap/idle.rs:37: Skipping IDLE in \"INBOX\" because there may be new mail."
2026-03-15T10:24:32.022Z core/event INFO "" 1 "src/scheduler.rs:384: IMAP loop iteration for inbox finished, keeping the session."
2026-03-15T10:24:32.024Z core/event INFO "" 1 "src/imap.rs:1472: Will use fallback ICE servers."
2026-03-15T10:24:32.025Z core/event INFO "" 1 "src/imap.rs:554: Not fetching from \"INBOX\"."
2026-03-15T10:24:32.243Z core/event WARNING "" 1 "src/download.rs:285: Failed to download message rfc724_mid=73bc616d-e126-40a4-b07f-042a8224038b@localhost: IMAP location for \"73bc616d-e126-40a4-b07f-042a8224038b@localhost\" post-message is unknown."
2026-03-15T10:24:32.475Z core/event INFO "" 1 "src/scheduler.rs:566: IMAP session in folder \"INBOX\" supports IDLE, using it."
2026-03-15T10:24:32.477Z core/event WARNING "" 1 "src/download.rs:285: Failed to download message rfc724_mid=73bc616d-e126-40a4-b07f-042a8224038b@localhost: IMAP location for \"73bc616d-e126-40a4-b07f-042a8224038b@localhost\" post-message is unknown."
2026-03-15T10:24:32.542Z core/event INFO "" 1 "src/scheduler.rs:566: IMAP session in folder \"DeltaChat\" supports IDLE, using it."