Friction: Fix reach plot.

src/View/Frictions/Window.py

@@ -136,6 +136,7 @@ class FrictionsWindow(PamhyrWindow):
         self.plot = PlotKPZ(
             canvas=self.canvas,
             data=self._reach.reach,
+            study=self._study,
             trad=self._trad,
             toolbar=None,
         )