1925371 - Bad download UX when default Downloads folder is full

Status: NEW

(Toolkit :: Downloads API, defect, P3)

Description

[Niklas Hambüchen]

Steps to reproduce:

1. Try to download a file (5 GB Ubuntu 24.05 .iso my case) that's larger than remaining disk space of the drive of the the default Downloads folder. Observe that to fail, filling up the drive.
2. In the settings, check [x] Always ask where to save file.
3. Retry the download, picking a folder of a different drive that has enough space.

I did this in a screenshare remote support session of a non-technical relative, who had booted into a Linux Mint 22 live DVD.

Actual results:

The download of (3) disappeared without any proper error message.

Expected results:

Multiple things:

• Firefox should warn the user before the download that there is not enough space. (The Content-Length response header was set for the download, so Firefox knows how much space is needed.)
• A clear error message should be shown when the download fails due to lack of space.

Related is the issue that Firefox writes temporary files the default Downloads folder at all, even though the user has explicitly chosen a different folder on a different drive. See Bug 1823139.

Firefox does that so that downloading already happens while the user chooses the file name, but it creates parts of the reported problems.

In any case, this bug is about the lack of proper error messages.

Comment 1

[Marco Bonardo [:mak]]

A couple possibilities:

1. If we can get content-length, we may better handle the case it doesn't fit
2. We may pre-emptively show a badge and a warning in the downloads panel stating "your download folder space is low, downloads may misbehave"