Transparent PNGs are being displayed at a too-low resolution, resulting in blurry images.
Example:
https://en.wikipedia.org/wiki/File:Psikyo-Koyori_artwork.png is a 239 × 421 pixel image, which should normally be displayed at full size both at the image page and when included as the lede image of an article (https://en.wikipedia.org/wiki/Koyori). In both cases, however, instead of using the full-size image (https://upload.wikimedia.org/wikipedia/en/a/ad/Psikyo-Koyori_artwork.png), a 120px version of the image is used instead (upload.wikimedia.org/wikipedia/en/thumb/a/ad/Psikyo-Koyori_artwork.png/120px-Psikyo-Koyori_artwork.png), resulting in a blurry image due to upscaling.
Reported via Discord and at https://en.wikipedia.org/wiki/Wikipedia:Village_pump_(technical)#Transparent_PNGs_appear_broken_on_wikipedia. This issue appears to be affecting many images, reportedly transparent PNGs.
The full image, as it is not smaller than the display size, should be used, and was prior to around march 12
