>>/518/
> I wasn't there when it happened but I am imagining it as a weird picture in which none of both sides connect match that well. 

I ain't sure if it's the first, but one of the earlist acknowledgements I can recall was a hub promo all the way back in 2011. It's a pardody of one of Katty Parry's songs. They made an extented version and sent it directly to EqD themselves. It even mentioned the word "brony". 

https://youtube.com/watch?v=pTPqjKk_xCo
Here it is posted on EqD's YT channel

https://www.equestriadaily.com/2011/05/extended-equestria-girls.html
Here is the link to the old EqD article on it, they were a far different animal back then.

Now, granted I am barelly awake right now and still sick and I only was in partial, not admiting it to myself orbit of  the fandom, so there maybe something huge that I am forgetting. Then again, you may have seen this already, making this post pointless