Probably the only people who know for sure will be the forum developers/maintainers.
However, looking at what you posted i'm wondering if the forum now filters out scripting attempts. That's actually a very good thing if it is as that is a huge security hole waiting to be breached.
I'm guessing what you were trying to post is a web link. If so, there's no reason that needs javascript or CSS. It's far better to not allow users to enter such things either. Use the link code that is described in the sticky. It's safer and neater.