optimization

src/textual/_compositor.py

@@ -276,7 +276,10 @@ class Compositor:
         resized_widgets = {
             widget
             for widget, (region, *_) in changes
-            if widget in common_widgets and old_map[widget].region.size != region.size
+            if (
+                widget in common_widgets
+                and not old_map[widget].region.same_size(region)
+            )
         }
 
         screen_region = size.region

src/textual/geometry.py

@@ -541,6 +541,18 @@ class Region(NamedTuple):
         width2, height2 = size
         return Region(x, y, min(width1, width2), min(height1, height2))
 
+    def same_size(self, region: Region) -> bool:
+        """Check if another region is the same size. Equivalent to `self.size == region.size`,
+        but a little faster.
+
+        Args:
+            region (Region): A region.
+
+        Returns:
+            bool: True if both regions are the same size, False if they are different sizes.
+        """
+        return self[2:] == region[2:]
+
     def expand(self, size: tuple[int, int]) -> Region:
         """Increase the size of the region by adding a border.