<image> doesn't come through in final PNG

Hi, I have multiple PNGs coming from URLs using href inside image tag. None of those images appear in final PNG

Line 12 in 5bcd474

    
               <image href="https://octodex.github.com/images/nyantocat.gif" width="500" height="500"/>

Okay so main issue is that it doesn't accept a URL with params. This seems like an oversight. I had to override the code above a bit to get it to work