Currently, image-rendering: crisp-edges is defined somewhat abstractly to just be:

The image must be scaled with an algorithm that preserves contrast and edges in the image,
and which does not smooth colors or introduce blur to the image in the process.
This is intended for images such as pixel art or line drawings.

It's allowed for this to just be identical to pixelated, but it can use more advanced upscaling algorithms if desired, like hq2x (I have no idea what the state of the art here is).

Is there any actual interest in making this do something different from pixelated? Or should I just fold it in as a legacy alias, like the older SVG keywords?

/cc @dholbert especially