Fix pickling issue when saving RGB gifs

src/mpl_stereo/AxesStereo.py

@@ -471,6 +471,13 @@ def wiggle(self, filepath: Union[str, Path], interval: float = 125,
             if yaxis_off:
                 ax.yaxis.set_visible(False)
 
+            # workaround for https://github.com/matplotlib/matplotlib/issues/28448
+            artists = ax.get_children()
+            for artist in artists:
+                if isinstance(artist, mpl.image.AxesImage):
+                    array = artist.get_array()
+                    artist.set_array(array.data.astype('float64'))
+
         def update(frame):
             axs[frame].set_visible(True)