optimize scroll

src/textual/scroll_view.py

@@ -82,10 +82,8 @@ def _size_updated(
             layout: Perform layout if required.
 
         Returns:
-            True if anything changed, or False if nothing changed.
+            True if a resize event should be sent, otherwise False.
         """
-        if self._size != size or self._container_size != container_size:
-            self.refresh()
         if (
             self._size != size
             or virtual_size != self.virtual_size
@@ -96,9 +94,8 @@ def _size_updated(
             virtual_size = self.virtual_size
             self._container_size = size - self.styles.gutter.totals
             self._scroll_update(virtual_size)
-            return True
-        else:
-            return False
+
+        return self._size != size or self._container_size != container_size
 
     def render(self) -> RenderableType:
         """Render the scrollable region (if `render_lines` is not implemented).

src/textual/widget.py

@@ -3695,8 +3695,9 @@ def _size_updated(
             layout: Perform layout if required.
 
         Returns:
-            True if anything changed, or False if nothing changed.
+            True if a resize event should be sent, otherwise False.
         """
+
         self._layout_cache.clear()
         if (
             self._size != size

src/textual/widgets/_option_list.py

@@ -824,7 +824,6 @@ def get_option_index(self, option_id: str) -> int:
             ) from None
 
     def render_line(self, y: int) -> Strip:
-        self._populate()
         assert self._lines is not None
 
         _scroll_x, scroll_y = self.scroll_offset