Occasionally when posting data the actual form content is missing. At first I thought this was a result of the web framework I'm working with, but reducing the error to a small python echo server I can manage to get the bug to trigger (I think. I might also be crazy).
To reproduce, download and run the small echo server, and submit the provided test file to the provided form. It generally takes a few times, but if you keep resubmitting the form you should eventually see a post that contained no data. Occasionally a post with only partial data will be read as well.
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small python echo server
Small echo server to dispaly safari's request headers.
Created attachment 20641 [details]
Simple form with file field to post
Example form that causes the error
Created attachment 20642
Largish test file helps exacerbate the problem.
I'm a fucking retard. Disregard this bug.