I was doing some hacky stuff with a psuedo-element to make posts "fade" into the background, but that had the downside of requiring a solid background color to fade it into, and didn't let you highlight text on the post body when faded.

With the mask-image property, I can cleanly fade out posts on the front page with whatever kind of background I want. To demonstrate, I made the background kinda wacky.

The downside here is that it doesn't work on IE, but since I use CSS vars anyway, I don't really care. IE is dead.