nenilein:

I really hate it when people confuse the terms “Canon”, “Headcanon” and “Alternate Universe”. 

“Canon”: Something that has been outright been stated in canon outside of a joke, in a way that unambiguously means this exact thing and nothing else.

“Headcanon”: It was never unambiguously specified in canon, but I interpret this on my own in a way that goes along with canon without contradicting it. 

“Alternate Universe”: My game, my rules. 

They are not interchangeable terms.