I have just passed through this question. I was kind of surprised, that OP "secured" a picture as we hide typical text-spoiler. Is this really necessary? I can't imagine, that a single image can become a spoiler and can reveal anything important to someone, who never watched (or read) something.
I'd like to edit this particular question, but I'm unsure, if this is correct decision.
Please, advise, if images can be a spoilers (and therefore should be hidden, as in given example)? Both, in case of this particular question and as a general rule, that should be used here.