Yeah, that happens sometimes when someone tries to manually copy and paste from a post, and accidently copies more than the text.
Without getting too technical, that loading image is actually present at all times; it's just invisible, and made visible temporarily when needed. So when you copy that area of the post, you can accidently copy the image itself, even if you can't see it. That's what happened here; it's basically just like putting any other image in your post.
Anyway, I've edited the post in question to remove the image. Thanks for the heads-up.
Without getting too technical, that loading image is actually present at all times; it's just invisible, and made visible temporarily when needed. So when you copy that area of the post, you can accidently copy the image itself, even if you can't see it. That's what happened here; it's basically just like putting any other image in your post.
Anyway, I've edited the post in question to remove the image. Thanks for the heads-up.