comment

src/textual/app.py

@@ -370,6 +370,8 @@ class App(Generic[ReturnType], DOMNode):
         self.css_path = css_paths
         self._registry: WeakSet[DOMNode] = WeakSet()
 
+        # Sensitivity on X is double the sensitivity on Y to account for
+        # cells being twice as tall as wide
         self.scroll_sensitivity_x: float = 4.0
         """Number of columns to scroll in the X direction with wheel or trackpad."""
         self.scroll_sensitivity_y: float = 2.0