But going a bit bigger picture, the problem is that we still use file extensions to denote file type.
However, there were many other reports of students going the more "normal" route of just uploading through their iPhones, which caused the website to outright hang.
That’s quite impressive actually and much more than I would expect from a browser’s <input type=“file”> control.
JPEG conversions will vary in quality and size. On some sites (e.g. a CMS), quality can be sacrified to stay within file size limits.
On other sites, like photo printing services, quality is much more important.
These may be unusual cases, but silent browser assumptions are still an overstep.
The server is saying it can't read the other file type, so the alternative is to fail.
Convert the image to a format the site accepts (jpg)?
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[OK] [Cancel]Also I'm not sure if you can generalize from your one relative to 99% of users.
What they did instead was to poorly reinvent the accept header in Javascript as follows:
(per https://news.ycombinator.com/item?id=23261598).