Windfury seems to have a range check on each single extra swing.
Windfury procs and only puts out its extra swings if the shaman is in range to do so.
This is not how it should be – once procced the extra swings should apply instantly regardless of range.
Edit: seems like its not necessary range but just gets activated on the next swing sometimes. Really scuffed stuff.
Will add footage later.
Update 3: Footage added on top.