Spoiler tag blur doesn't always do a good job of actually hiding the spoiler

This morning, a game that will be shown in the upcoming Nintendo Direct leaked. I wanted to post about it on my Discord, so I uploaded a spoiler tagged image: 

Even with the blurred image, it's pretty obviously a picture of Kirby.

It would be nice to at least have the option of spoiler tagged images that completely obscure the image from view. Or perhaps a preview of how the spoiler will look before you post it.