I'm very interested in fixing this quickly for you, but I have a question: Would it be helpful to have the information either in the tutorial section (the first screen that pops up unless you check the "never again" box) or somewhere else on the page (like after the header "Upload Wizard" at the top of the screen)? Putting text right in the middle of the form isn't really a previously-considered use case, so it would take some indelicate javascripting.

But, for your troubles, I'll throw in an accept= attribute for the file inputs, which should make it easier for your *browser* to help you out, if your browser actually implements that feature. Essentially, your browser will have some indication of what the server expects, and could filter the file browser accordingly. See https://developer.mozilla.org/En/HTML/Element/Input#attr-accept and http://stackoverflow.com/a/181291 for more information on that particular half-solution.

would be best if it would be similar to the old upload tool: e.g.

[[Commons:File types|Permitted file types]]: png, gif, jpg, jpeg, xcf, mid, ogg, ogv, svg, djvu, tiff, tif, oga.

Also, from https://translatewiki.net/wiki/Thread:Support/Upload_wizard_upload_button: "the UploadWizard supports one or several files. Since this cannot be known in advance, the message must cover both case".
Technically if one selects multiple media it's correct to say one has selected one [at least], while it's not true of the contrary; non-verbose translatable options needed.

Sorry, strike the last comment. Wrong bug.

Thehelpfulone, now that each failed upload can be removed piecemeal, is this still an issue?

Thehelpfulonewiki wrote:

Sorry, I haven't uploaded anything in a while - which file types do we accept for images now then?

Mark Holmquist: You assigned this issue to you in 2012. Could you please provide a status update and inform us whether you are still working (or still plan to work) on this issue?
Only in case you do not plan to work on this issue anymore, should the assignee be set back to default and the bug status changed from ASSIGNED to NEW/UNCONFIRMED? Thanks.

mtraceur: Can you answer comment 6 and comment 7, please?

Sorry, Andre.

I think there's a configuration variable that will tell you what file types we're allowed - not sure off the top of my head what it is, but it exists.

I'm unassigning, I think this could be a useful thing for a new contributor to take on.

FYI we are now living in a world where the accept attribute could be useful for most of our users:

http://caniuse.com/#search=accept

We "only" have file extensions in config, so we can use it:

https://developers.whatwg.org/states-of-the-type-attribute.html#attr-input-accept

But we will break all uploads on IE11 mobile (big loss there) and not change the experience for Safari and a few other minor browsers.

Maybe good for GCI?

In T38743#1849304, @MarkTraceur wrote:

FYI we are now living in a world where the accept attribute could be useful for most of our users:

http://caniuse.com/#search=accept

We "only" have file extensions in config, so we can use it:

https://developers.whatwg.org/states-of-the-type-attribute.html#attr-input-accept

But we will break all uploads on IE11 mobile (big loss there) and not change the experience for Safari and a few other minor browsers.

Maybe good for GCI?

WFM.

FYI we are now living in a world where the accept attribute could be useful for most of our users:

Yes, that's what most websites do nowadays in my experience.