Fails to parse valid png with 'unknown filtered scanline'

[YenTheFirst]

The attached image appears to be a valid png (browsers and image editors can open it), but PNG.js can't parse it, returning an error 'unknown filtered scanline'.

This appears to be a different parsing problem, so I'm opening it up as a second issue

(url = https://f.cloud.github.com/assets/444387/117028/ac4f8486-6c17-11e2-845b-85e7234f6211.png)

[photopea]

Hi, there are about 15 PNG libraries on Github, which haven't been updated for years. That's why I wrote my own library UPNG.js - maybe you can use it instead. https://github.com/photopea/UPNG.js I just tested your image and it was parsed correctly (with UPNG.js).