null offset

src/textual/geometry.py

@@ -322,7 +322,7 @@ class Region(NamedTuple):
 
         if region in window_region:
             # Region is already inside the window, so no need to move it.
-            return Offset(0, 0)
+            return NULL_OFFSET
 
         window_left, window_top, window_right, window_bottom = window_region.corners
         region = region.crop_size(window_region.size)