I think it's pretty rare for me to dream about FH. Usually, it might involve something more specific, I think, like conversations, roleplays, etc.
Unless I have it on my mind for some reason and enough, no, I don't. Not the game, anyway, but maybe I'll dream about people I've met on there, like my best friends. :{o Or the roleplay that started there.
...I'm sure I have dreamed about it, though, in the past, since I've had good memories, good moments, good friends, a nice group, etc. I've had bad memories, bad moments, and bad friends as well, I figure I should mention, but that doesn't matter much to the topic. I'm just saying since I used to spend a lot of time in-game, I honestly don't doubt I have dreamed about it. x3 In fact, I recall, faintly, dreaming when I was first getting into it.
Nothing clear, though.