And you will break the window isnt accepted? i'll explain my thinking. so say for example you and your dad are playing baseball in your backyard. (i used this example because it is most common.) then dad says ''if we keep playing here you will break the window'' but apparently, that is not correct because duolingo corrected me by saying instead: ''you are going to break the window'' what the heck is the difference?!
The difference is that You are going to break the window is Near future and You will break the window is Future, a distinction that exists both in English and French. There is a difference between the two sentences (in French and in English), so we translate the two sentences differently.