I downloaded the file and it's a jpg with a png extension:
vividvervet_sylviaritter_web_by_sylviaritter-da8puk4.png: JPEG image data, JFIF standard 1.01, resolution (DPCM), density 236x236, segment length 16, baseline, precision 8, 752x1063, frames 3
I renamed the file to jpg and the image immediately appears in the gallery app.
I downloaded the file and it's a jpg with a png extension: sylviaritter_ web_by_ sylviaritter- da8puk4. png: JPEG image data, JFIF standard 1.01, resolution (DPCM), density 236x236, segment length 16, baseline, precision 8, 752x1063, frames 3
vividvervet_
I renamed the file to jpg and the image immediately appears in the gallery app.