Friction: Fix open stricker edit.

src/View/Frictions/Window.py

@@ -240,17 +240,15 @@ class FrictionsWindow(PamhyrWindow):
         self._table.redo()
 
     def edit_stricklers(self):
-        strick = self.sub_win_filter_first(
-            "Stricklers",
-            contain=[]
-        )
+        if self.sub_window_exists(
+            StricklersWindow,
+            data=[self._study, self.parent.conf]
+        ):
+            return
 
-        if strick is None:
         strick = StricklersWindow(
             study=self._study,
             config=self.parent.conf,
             parent=self
         )
         strick.show()
-        else:
-            strick.activateWindow()