docstring

Author: willmcgugan

src/textual/app.py

@@ -715,6 +715,9 @@ def animator(self) -> Animator:
     def screen(self) -> Screen:
         """Screen: The current screen.
 
+        Returns:
+            The currently active (visible) screen.
+
         Raises:
             ScreenStackError: If there are no screens on the stack.
         """