This bug is caused by Unity's nux windows being stacked below the fullscreen window.
The bug remains in Unity 6.0 however 6.0 honours the stacking order much better, so you don't even see the dash in that version.
This bug is caused by Unity's nux windows being stacked below the fullscreen window.
The bug remains in Unity 6.0 however 6.0 honours the stacking order much better, so you don't even see the dash in that version.