@sijad this is Flarum though, not Discourse. Every other piece of forum software out there has spoiler BB Code that hides content when used (I've never seen it just blurred due to some posts been spoilered due for image or post size, something that would be pointles with your extension as it stands now) and never seen it as details.
As to the replacing image, no I wasn't talking about Details at all, I don't care about details, I was asking aboput it for spoilers.
All I'm asking is how about we have a spoilers extension as per your original one but with the ability to either have an image or text indicating it's a spoiler when no title has been specified in the title code.