Hmmmm, were you a bit high when you typed this??
LOLno just kidding. To give a serious answer to your question..
It sounds like a plain glitch to me. What platform are you running FH on when this happens? Have you tried fooling around with your display settings or blocklist though? I recognize it kinda since it happened to me in South Pole a few times. I was to observe a chat from someone who looked like he was talking to himself while another person was just next to him I couldn't see. I run it on Mac myself where this can happen, other times I use it on Windows without a problem. It happens... Neither I would think they must've blocked you, unless they had a good reason to. Maybe it's handy to try and reset some stuff? Hope that might help as it did for me slightly. c:
Well, it's rather common for OpenGL not to work on Windows so as you say it (although it depends on the running system what to accept). So my advise to you not to try that again ever lol. Good luck with that reset and if the issue still occurs, feel free to continue explaining it here!