fix(reports): add per-tile animation wait to prevent partial ECharts renders in tiled screenshots (#40694)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

superset/utils/screenshot_utils.py

@@ -89,6 +89,7 @@ def take_tiled_screenshot(
     element_name: str,
     tile_height: int,
     load_wait: int = 60,
+    animation_wait: int = 0,
 ) -> bytes | None:
     """
     Take a tiled screenshot of a large dashboard by scrolling and capturing sections.
@@ -98,6 +99,7 @@ def take_tiled_screenshot(
         element_name: CSS class name of the element to screenshot
         tile_height: Height of each tile in pixels
         load_wait: Seconds to wait for charts to load per tile (default 60)
+        animation_wait: Seconds to wait for chart animations per tile (default 0)
 
     Returns:
         Combined screenshot bytes or None if failed
@@ -174,6 +176,12 @@ def take_tiled_screenshot(
                     load_wait,
                 )
 
+            # Wait for chart animations (e.g. ECharts) to finish after spinner clears.
+            # The global animation wait before tiling only covers the first tile;
+            # subsequent tiles need their own wait after data loads.
+            if animation_wait > 0:
+                page.wait_for_timeout(animation_wait * 1000)
+
             # Calculate what portion of the element we want to capture for this tile
             tile_start_in_element = i * tile_height
             remaining_content = dashboard_height - tile_start_in_element

superset/utils/webdriver.py

@@ -369,6 +369,7 @@ class WebDriverPlaywright(WebDriverProxy):
                             element_name,
                             tile_height,
                             load_wait=self._screenshot_load_wait,
+                            animation_wait=selenium_animation_wait,
                         )
                         if img is None:
                             logger.warning(

tests/unit_tests/utils/test_screenshot_utils.py

@@ -371,3 +371,29 @@ class TestTakeTiledScreenshot:
 
         sig = inspect.signature(take_tiled_screenshot)
         assert sig.parameters["load_wait"].default == 60
+
+    def test_per_tile_animation_wait_called_per_tile(self, mock_page):
+        """animation_wait adds an extra wait per tile after the spinner check."""
+        with patch("superset.utils.screenshot_utils.combine_screenshot_tiles"):
+            take_tiled_screenshot(
+                mock_page, "dashboard", tile_height=2000, animation_wait=5
+            )
+
+        # 3 tiles × (1 scroll settle + 1 animation wait) = 6 total calls
+        assert mock_page.wait_for_timeout.call_count == 6
+
+        animation_calls = [
+            call
+            for call in mock_page.wait_for_timeout.call_args_list
+            if call[0][0] == 5 * 1000
+        ]
+        assert len(animation_calls) == 3
+
+    def test_animation_wait_default_is_zero(self):
+        """animation_wait defaults to 0 so no extra per-tile wait by default."""
+        import inspect
+
+        from superset.utils.screenshot_utils import take_tiled_screenshot
+
+        sig = inspect.signature(take_tiled_screenshot)
+        assert sig.parameters["animation_wait"].default == 0