diff --git a/CHANGELOG.md b/CHANGELOG.md
index 65abbd3d00..03790601eb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -29,6 +29,9 @@ This project adheres to [Semantic Versioning](http://semver.org/).
     - Note: Safari 15, Chrome 56, Firefox 51 and later are now required for map traces
 - Update `hex_to_rgb` function to raise error for invalid-length hex codes, and emit warning for hex codes containing alpha [[#5729](https://github.com/plotly/plotly.py/pull/5729)], with thanks to @dylanpulver for the contribution!
 
+### Fixed
+- Fix `FigureWidget` state synchronization bug where frontend modifications to array properties (like `layout.shapes`) failed to properly update the Python property cache and occasionally surfaced `Undefined` objects [[#5689](https://github.com/plotly/plotly.py/issues/5689)]
+
 ## [7.0.0] - 2026-08-25
 
 ### Fixed
diff --git a/plotly/basedatatypes.py b/plotly/basedatatypes.py
index d81ba0950c..121ae52b73 100644
--- a/plotly/basedatatypes.py
+++ b/plotly/basedatatypes.py
@@ -5458,6 +5458,16 @@ def _dispatch_change_callbacks(self, changed_paths):
         -------
         None
         """
+        # Invalidate cache for changed compound array properties so that they are 
+        # reconstructed from the underlying properties dictionary on the next access.
+        # We only pop from _compound_array_props because compound arrays are immutable 
+        # tuples that must be rebuilt to reflect added or removed elements.
+        for path in changed_paths:
+            if len(path) > 0:
+                prop = path[0]
+                if prop in self._compound_array_props:
+                    self._compound_array_props.pop(prop, None)
+
         # Loop over registered callbacks
         # ------------------------------
         for prop_path_tuples, callbacks in self._change_callbacks.items():