Guild Wars 2

Not sure if it has been mention but i noticed that if an elem has a swift buff. It does not seem to stack with mesmers swift buff Only. But it works other way around. Is this a bug or is it how its ment to work

Not sure if its meant to be this way but I’ve noticed too that the “ground based” swift buffs dont seem to stack. Probably to avoid people straddling them back and forth and gaining a huge swift stack.