What is this static.ak.facebook.com popup?

I haven't taken screenshots so please bear with me. Last night while browsing, I've been bombarded with a popup with content along these lines: "static.ak.facebook.com Your player is out of date. Click to update your player now!"; the only thing to click was "Ok". Needless to say, I didn't click it and just did a force quit on my browser. This issue has been happening on both my Safari and Google Chrome browsers. On top of that, my daughter received a similar popup (saying that her player was outdated and needs an update) only this time it claimed it was from YouTube; we didn't click that either. Does anyone have any idea what could be causing this, or what the intention behind it?