Ugh, I’d say that’s a bad UI/security bug
@codinghorror what do you think about this:
Hi, I’m a secret spoiler that you really want to see!
(@crenquis’s version above manages to do away with the red line, by magic tricks.)
(Also, it doesn’t look like you can @-someone, like @codinghorror, in a spoiler. Or at least, the name doesn’t turn into a link