- Mentioned Here
- rEUWIe43d3d16e984: Merge "jQuery 1.9 compatibility fixes"
T48741: UploadWizard unable to override "similar name"/"same name" detection warning
T71691: Ability to recover from an Expired session (badtoken)
T92801: UploadWizard does not preserve the order of the images between upload and later steps
T94562: Chunked/stashed uploads fail for some pdf and djvu files: "No specifications provided to ArchivedFile constructor."
T101616: Flickr upload broken (with various error messages)
T106968: UploadWizard form gets to deadlock when the file title is not accepted
It having been ignored for more than a year doesn't mean it's "probably not an issue anymore", especially if no unrelated changes have been made that might have fixed it indirectly. I have no recent experience of the problem because I have been using an external uploader (VicuñaUploader) for quite a while to specifically avoid the issues. Don't think "don't use our own uploader, use something else" is how we want to solve issues with the UploadWizard.
I just spent a lot more time than it would be reasonable playing with an old-ish version of UploadWizard, e43d3d16e98488ba67a7731f3a1a18bcc10d9eaa (2014-05-22), which seems to be the oldest one that works with current MediaWiki. I couldn't reproduce this problem, just like I can't reproduce it with modern UploadWizard.
I don't think it would be a good use of our time (and donor money ;) ) to continue chasing this phantom. We have fixed a number of important issues relating to uploading in recent months (including T48741, T71691, T94562, T106968, T101616, T92801), but none of them looks related to this one. I trust that you understand that it's hard to tell which of the other ~800 changes to UploadWizard since when you filed this bug could have affected this. Especially since we don't actually know what the cause was.
If a different uploader satisfies your needs better than UploadWizard, then by all means do use it, I don't see why not. UW tries to cater to beginner users more than advanced ones in some places, perhaps unlike Vicuña.
According to https://commons.wikimedia.org/wiki/Special:ListFiles/Tim_Adams, the original reporter "fixed" the issue by stopping uploading PNG files: he only uploads in JPG format now. It seems the failure was very consistent for him, I'll ask him to try again.