Danbooru: bd07fdf9b52c0df407bcd9f5d7b28c0f, png, 945 x 1364, 1668.2 KB
Pixiv: 7334ef4e511881a7ea6887fedae43766, jpg, 655 x 945, 162.4 KB
Actually the source should be Twitter, this is where I got the image from. I used the pixiv URL only to fetch post information; I suppose that Danbooru did not recognize the Twitter image URL after I switched it back because I already clicked fetch post information and did not reload the upload page.