It seems like Twitter has, in the past week or so, changed something about how their upload system handles PNGs. Around the same time a bunch of Twitter artists who previously consistently uploaded PNGs started having all of their uploads become Twitter's very lossy JPGs. (for example, himura kiseki's posts in the weeks past this point)
Attempting to upload your own PNGs via their system seems to get them converted the vast majority of the time, but not all of the time. I can't really nail down any consistent factors between the files that avoid conversion, but there's probably something obvious I'm missing.
I was wondering if anyone could figure out what exactly differs between the files that do and don't get converted to JPG and if there's actually any possibility of accessing the original PNG files. .png and .png:large versions of all of these posts do exist, but as far as I can tell those urls always existed for JPG posts, and are visibily just the jpeg compressed versions converted back to PNG.
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