Mine has this too, got told to turn my washer jet to the '2 o clock' position rather than straight up! which I have.
this helped anyone? or is it just a vast amount of condensation that builds it up?
Also wanting to replace the rear window with the darkened OEM window, I think TT did this!... again, same situation with the spoiler, has to ripped off!
![scared :scared:](https://www.mk5golfgti.co.uk/forum/Smileys/newsmileys/scared.gif)