Unfortunately there's no built-in option like that on this forum, as I've seen on other forums. It'd be a nice thing to have, but I think Fr. Anastasios and company are doing all they can just to keep things that they already have running smoothly--not from lack of know-how, but just from lack of time/resources. Fwiw, you could always manually hide the text by changing the color to white, for example:
*Spoiler: highlight hidden text below*
This is a spoiler.
Yes, it is.
That is to say, I think it is.
Maybe it is.